Asparagus

Asparagus

Growing Asparagus

Interior and Coast

Jersey Knight, Millenium (Trial).

See your seed dealer for the latest variety recommendations.

Growers may purchase well-graded, 1-year-old crowns from reliable sources or nurserymen, or grow their own crowns from seed provided irrigation is available. Seed should be sown in the late spring in well-prepared fertile soil which is around 21°C at depth of seeding. Seed 2.5 to 4 cm deep and 10 to 12.5 cm apart in rows 60 to 90 cm apart. About 5.5 kg of seed will be sufficient to sow a hectare of nursery (2.2 kg of seed per acre) and each kg of seed will produce 22,000 usable crowns.

Crowns

Plant only into fertile well-drained loams, sandy loams and muck soils which are free of perennial weeds.

Use only the largest and best crowns. Discard any weak crowns. Under dryland farming conditions, 13,500 crowns per hectare (5460/acre) are required. Plant in furrows 120 cm apart, 20 to 25 cm deep, and with the crowns 60 cm apart. On irrigated land, 27,500 crowns per hectare (11,100/ acre) or more are required. Plant in furrows 120 cm apart, 20 to 25 cm deep, and with the crowns 30 cm apart.

Crowns should be treated before planting as described under Fusarium Wilt and Root Rot.

Spread out the roots and cover with not more than 4 cm of soil. Fill in furrow gradually by cultivating as plants grow. Do not harvest until the second year, and then only for 2 weeks if the fern growth was strong the previous season.

Transplants

The use of greenhouse grown transplants may be feasible especially when using expensive hybrid seed. Seeds are planted individually in blocks, modules or flats in February. Transplants are planted to the field in mid-May.

Establishment Year

A soil test is necessary to determine phosphate and potash requirements.

For phosphate and potash recommendations based on soil test results, consult the Vegetable Production Guide: Nutrient Management (PDF).

Broadcast 60 kg/ha (24 kg/acre) of the nitrogen before planting and work into the soil. In June and July side-dress the emerged spears with 10 kg/ha (4 kg/acre) applications of nitrogen. All of the required phosphate and potash should be banded below the crowns prior to planting.

Established Plantings

Apply up to 120 kg/ha (48 kg/acre) nitrogen yearly unless soil analysis suggests differently. Apply half the nitrogen and other required nutrients in early spring, prior to harvesting. Broadcast the remainder of nitrogen immediately after harvest.

Healthy two-year-old plantings may be lightly harvested for 10 to 14 days; three-year-old plantings for 4 weeks and mature plantings for 6 weeks. A mature planting should produce about 100 kg/ha per picking over 30 picking days for a total yield of 3,000 kg/ha.

For fresh market sales, the crop should be hydro-cooled immediately after harvest. Forced-air cooling is also an option. Failure to reduce the field temperature promotes growth, causing loose tips.

Recommended storage and shipping temperature is 0°C, with a relative humidity of 95%.

 

Asparagus Weed Management

Seed-bed Asparagus: Herbicide Application Rates

Product Rate PHI* Comments

Venture L

(fluazifop-P-butyl)

Group 1
barnyard grass (2-5 leaf stage):
0.8 L/ha (0.32 L/acre)

proso millet (2-5 leaf):
1.0 L/ha (0.4 L/acre)

foxtails (2-4 leaf):
1.4 L/ha (0.56 L/acre)

quackgrass (3-5 leaf):
2.0 L/ha (0.8 L/acre)


 

 

N/A

  • See Second Year and Established Plantings Before Spear Emergence or After Last Cutting table on this page for more uses.
  • Annual bluegrass and broadleaved weeds are not controlled.
  • Make only one broadcast application per year.
  • Do not cultivate between rows until 5 days after application.
  • Apply in 50 to 200 L/ha (20 to 80 L/acre) water at 200 to 300 kPa.
  • Warning: Women capable of bearing children should avoid exposure to Venture.
  • Do not handle more than 50 kg a.i. (400 L product) per day.
  • Use a closed cab when applying more than 33 kg a.i. (264 L product) per day.
  • Do not re-enter treated area for 12 hours.

Sandea

(halosulfuron)

Group 2
35 to 105 g/ha (14.2 to 42.5 g/acre)

Apply in 140 L/ha (57 L/acre) of water.
N/A
  • Use post-emergence.
  • To prevent crop injury, do not use with an adjuvant.
  • Controls broadleaf weeds including ladysthumb, wild mustard, yellow nutsedge and redroot pigweed.
  • Suppresses shepherd's purse and smartweed.
  • Will not control ALS-inhibitor resistant weeds.
  • Applications should be made to actively growing weeds at the heights defined in the "USE RATE GUIDE" section of the label.
  • Treat actively growing nutsedge plants at the 3 to 5 leaf stage.
  • Do not use more than 140 g/ha (57 g/acre) of product per season.
  • Do not apply more than two times per season.
  • Wait to overhead sprinkler irrigate for 2 to 3 days after application
  • If a timely soil cultivation is necessary to improve control, wait 7 to 10 days after treatment.
  • A sequential application may be necessary for some annual and perennial weeds.
  • Sequential application should be repeated in 21 days.
  • Do not enter treated area for 12 hours.

Sinbar

(80% terbacil)

Group 5
375 g/ha (152 g/acre)

Apply in at least 200 L/ha (80 L/acre) of water
N/A
  • Apply within 2 days of planting seed.
  • Do not apply within 2 weeks before or after an application of Venture.
  • Do not apply to soils containing less than 1% organic matter.
  • Crop injury may occur if applied on weak or diseased plants.
  • See label for planting depth instructions based on soil texture.
  • Do not enter treated area for 12 hours.

Lorox L

(linuron)

Group 7
2.08 to 4.17 L/ha (0.84  to 1.69 L/acre)
N/A
  • Make a single application, pre-emergence of asparagus seedlings.
  • Do not use on coarse-textured soils with less than 2% organic matter.
  • Requires 3 to 5 cm of irrigation or rainfall within 7 days of application.
  • Will not control atrazine resistant weeds.

Ignite 15 SN

(glufosinate ammonium)

Group 10
2.7 to 5.0 L/ha (1.1 to 2.0 L/acre)

Apply in 110 to 330 L water/ha (45 to 135 L/acre) at 275 to 310 kPa
N/A
  • As recommended in the Vegetable Production Guide: Pest Management (PDF, 1.2 MB), the Stale Seed-bed Technique may be used prior to asparagus seedling emergence to kill the first flush of weeds in nursery beds.
  • Rainfall within 4 hours of application may reduce effectiveness.
  • Do not handle with bare hands or with leather or cloth gloves.
  • Do not enter treated area for 12 hours.

Guardsman/ Agricultural Weedkiller

No. 1 (mineral spirits)
500 L/ha
(200 L/acre)
N/A
  • Apply when asparagus seedlings are 5 cm high and weeds have 3 to 4 true leaves.
  • Controls chickweed, bluegrasses, barnyard grass, redroot pigweed, lamb’s quarter and purslane.
  • Pineappleweed and wormseed mustard are not controlled consistently.
  • Crop damage may result if sprays are applied in hot, dry weather, or when plants are wet with rain or dew.
  • Note: Other solvents may cause crop damage.
  • See label for use in the producing field.

*PHI = Pre-harvest interval
BUFFERS – Refer to product label for buffer requirements, and consult the Vegetable Production Guide: Pesticide Regulations and Safety (PDF).
PESTICIDE GROUP DETAILS – see the Vegetable Production Guide: Pesticide Toxicity Table (PDF).

First Year Crowns and New Plantings: Herbicide Application Rates

Product Rate PHI* Comments

Sandea

(halosulfuron)

Group 2
35 to 105 g/ha (14.2 to 42.5 g/acre)

Apply in 140 L/ha (57 L/acre) of water
1
  • Use post-emergence/post transplant.
  • For first year transplants, apply no sooner than six weeks after fern emergence.
  • See comments in "Seed-bed Asparagus" section of this chapter.

Devrinol 50-DF

(napropamide)

Group 15

4.5 to 9.0 kg/ha (1.8 to 3.6 kg/acre)

Apply in 200 to 900 L/ha (80 to 365 L/acre) of water

N/A
  • Apply pre-emergent to crop and weeds for control of annual grassy and broadleaved weeds.
  • See label for listed weeds and rates.
  • Make only one application per season.
  • Irrigate if rainfall does not occur within two days of application.
  • Use the lower rate on coarse-textured sandy and sandy-loam soils.
  • Do no use on soils with more than 10% organic matter.
  • There is a 12 month plant back restriction on crops not found on the label.
  • Do not enter treated area for 12 hours.

Devrinol 2-XT

(napropamide)

Group 15

9.38 to 18.75 L/ha (3.80 to 7.60 L/acre)

Apply in 200 to 900 L/ha (80 to 365 L/acre) of water

N/A
  • Apply pre-emergent to crop and weeds for control of annual grassy and broadleaved weeds.
  • See label for listed weeds and rates.
  • Make only one application per season.
  • Irrigate if rainfall does not occur within two days of application.
  • Use the lower rate on coarse-textured sandy and sandy-loam soils.
  • Do no use on soils with more than 10% organic matter.
  • There is a 12 month plant back restriction on crops not found on the label.
  • Do not enter treated area for 12 hours.

*PHI = Pre-harvest interval
BUFFERS – Refer to product label for buffer requirements, and consult the Vegetable Production Guide: Pesticide Regulations and Safety (PDF).
PESTICIDE GROUP DETAILS – see the Vegetable Production Guide: Pesticide Toxicity Table (PDF).

Second Year and Established Plantings Before Spear Emergence or After Last Cutting: Herbicide Application Rates

Product Rate PHI* Comments

Venture L

(fluazifop-P-butyl)

Group 1
barnyard grass (2-5 leaf stage):
0.8 L/ha (0.32 L/acre)

proso millet (2-5 leaf):
1.0 L/ha (0.4 L/acre)

foxtails (2-4 leaf):
1.4 L/ha (0.56 L/acre)

quackgrass (3-5 leaf):
2.0 L/ha (0.8 L/acre)


 

 


 

 

1
 

 

  • Use on established plantings only.
  • Do not treat spears during harvest.
  • See Seed-bed Asparagus table on this page for more uses.
  • Annual bluegrass and broadleaved weeds are not controlled.
  • Make only one broadcast application per year.
  • Do not cultivate between rows until 5 days after application.
  • Apply in 50 to 200 L/ha (20 to 80 L/acre) water at 200 to 300 kPa.
  • Warning: Women capable of bearing children should avoid exposure to Venture.
  • Do not handle more than 50 kg a.i. (400 L product) per day.
  • Use a closed cab when applying more than 33 kg a.i. (264 L product) per day.
  • Do not re-enter treated area for 12 hours.

Poast Ultra

(sethoxydim)
 
Group 1

Annual grasses (incl. volunteer cereals):

320 mL/ha (130 mL/ac)

Annual grasses & quackgrass suppression:

470 mL/ha (190 mL/ac)

Quackgrass:

1.1 L/ha (445 mL/ac)

40
  • For control of annual grasses and quackgrass suppression, add Merge adjuvant using a rate of 0.5 - 1.0 L/ha (0.2 - 0.4 L/ac).
  • For control of quackgrass, add Merge adjuvant using a rate of 1.0 - 2.0 l/ha (0.4 - 0.8 L/ac).
  • Apply in 50 to 100 L/ha (20 to 40 L/acre) of water at 240 kPa pressure.
  • See label for water volume and pressure when weed infestations or crop canopies are dense.
  • Does not control annual bluegrass.
  • Apply when annual weeds are in the 1 to 6 leaf stage and quackgrass is in the 1 to 3 leaf stage.
  • Observe a 30 day plantback interval for crops not listed.
  • Do not enter treated area for 12 hours.

Sandea

(halosulfuron)

Group 2
35 to 105 g/ha (14.2 to 42.5 g/acre)

Apply in 140 L/ha (57 L/acre)
1
  • May be applied post-emergence to the weeds before or during the harvesting season.
  • See comments in "Seed-bed Asparagus" herbicide table of this guide for post-emergence application before harvesting.
  • See comments in "After Last Cutting" section of this chapter for post harvest directions.

Bonanza 480

(trifluralin)

Group 3
2.1 to 4.2 L/ha (0.8 to 1.7 L/acre)

Apply in at least 100 L/ha (40 L/acre) water
N/A
  • Use only on established plantings of 3 years or older.
  • Rates depend on soil type, see label for more detail.
  • For control of germinating annual grasses, lamb’s-quarters, chickweed and redroot pigweed.
  • Do not use on soils with less than 2% or more than 15% organic matter.
  • Do not apply to wet soils that may flood.
  • Incorporate within 24 hours application, in the same direction of application at a depth of 8 to 10 cm.
  • If manure is spread prior to application, ensure it has been thoroughly mixed into soil with at least 2 tillage operations prior to application.
  • Do not enter treated area for 12 hours.

MCPA Amine 500

(MCPA)

Group 4
3.75 L/ha (1.5 L/acre)

Apply in 50 to 200 L/ha (20 to 80 L/acre) of water at 200 to 350 kPa
N/A
  • Apply following a cultivation just before first spears appear.
  • Controls most annual broadleaf weeds, and set back field bindweed, Canada thistle and perennial sow thistle.
  • Weeds are most sensitive when they are rapidly growing.
  • A second application may be made immediately after the cutting season at least 21 days after first application.
  • Do not enter treated area for 12 hours.
  • Use drop nozzles to avoid spraying the fern.

Sencor 75 DF

(metribuzin)
 
Group 5
1.5 kg/ha (0.6 kg/acre)

Apply in 100 to 300 L/ha (40 to 120 L/acre) of water at 150 to 275 kPa
14
  • Apply in early spring before spears emerge and/or following last cutting.
  • If the field is to be disced, apply after discing but before crop emerges.
  • Do not use on coarse soils with less than 2% organic matter.
  • Do not use on newly seeded asparagus nor on young plants during the first growing season after setting crowns.
  • Do not apply once crop has emerged.
  • Controls many annual grassy and broadleaved weeds.
  • Do not enter treated area for 12 hours.

Sencor Solupak 75 DF

(metribuzin)

Group 5
1.5 kg/ha (0.6 kg/acre)

Apply in 100 to 300 L/ha (40 to 120 L/acre) of water at 150 to 275 kPa
14
  • Apply in early spring before spears emerge and/or following last cutting.
  • If the field is to be disced, apply after discing but before crop emerges.
  • Do not use on coarse soils with less than 2% organic matter.
  • Do not use on newly seeded asparagus nor on young plants during the first growing season after setting crowns.
  • Do not apply once crop has emerged.
  • Controls many annual grassy and broadleaved weeds.
  • Do not enter treated area for 12 hours.

Simazine 480

(simazine)

Group 5
4.7 to 7 L/ha (1.9 to 2.8 L/acre)

Apply in 300 L/ha (120 L/acre) of water.
7
  • Apply in spring to established fields after discing, but prior to weed and spear emergence, and at least 7 days before first cutting.
  • A 2nd application may be made after harvest completion if weeds are removed.
  • In arid regions where Simazine would break down very slowly in the soil (especially under non-irrigated conditions), only one application per year is advised.

Princep Nine-T

(simazine)

Group 5
2.5 to 3.75 kg/ha (1.0 to 1.5 kg/acre)

Apply in 300 L/ha (120 L/acre) of water at 200 to 300 kPa.
7
  • Use the lower rates on sandy or silt loams; the higher rates on silty-clay to clay loams.
  • Rainfall or irrigation is necessary to activate simazine.
  • Do not apply during cutting season.
  • Resistant populations of redroot pigweed, lamb’s-quarters, groundsel and other weeds may develop from the continuous use of simazine over several years.
  • Do not enter treated area for 12 hours.

Sinbar

(terbacil)

Group 5
375 g/ha (152 g/acre)

Apply in at least 200 L/ha (80L/acre) of water
5
  • Use prior to spear emergence for annual grassy and broadleaved weed control.
  • Application may be made immediately after clean cutting.
  • Apply before annual weeds emerge or grow more than 5 cm tall or across.
  • Apply only once per season.
  • Do not use on soils containing less than 1% organic matter or on areas where subsoil or roots are exposed.
  • Crop injury may occur if used on weak, diseased or slow-growing plants.
  • Use only on estabilished platings of 3 years or older.
  • Do not enter treated area for 12 hours.
  • Do not plant treated areas to any crop within 2 years of the last application.

Lorox L

(linuron)

Group 7
3.4 to 4.5 L/ha (1.4 to 1.8 L/acre)

Apply in 300 L/ha (120 L/acre) of water
N/A
  • Make a single application immediately after 1st discing, before asparagus emerges.
  • Do not use on coarse-textured soils with less than 2% organic matter.
  • Requires 3 to 5 cm of irrigation or rainfall within 7 days of application.
  • Treatment may be repeated after the last cutting.
  • Will not control atrazine resistant weeds.
  • Can also be used for 1st year crowns.
  • For use on seedling asparagus, see Seedbed Asparagus  table for details on rate and tankmix directions.

Karmex DF/ Diurex 80 WDG

(diuron)

Group 7
1.1 to 2.25 kg/ha (0.4 to 0.9 kg/acre) in light sandy or low clay and organic matter soils

OR

2.25 to 4.50 kg/ha (0.9 to 1.8 kg/acre) in soils high in clay or organic matter
N/A
  • Apply to established asparagus only, no earlier than 4 weeks before spear emergence and no later than the early cutting period.
  • Controls weed seedlings for pigweed, lamb’s quarter, crabgrass, foxtail and ragweed.
  • Apply in 250 to 400 L/ha (100 to 160 L/acre) of water.
  • Requires rainfall or irrigation to be carried into the root zone of germinating weeds.
  • If irrigation is used, apply only once at 4.5 kg/ha (1.8 kg/acre) in late September or October.
  • A second application may be made immediately following completion of harvest, if rainfall is expected.
  • When making two applications in one season do not exceed 3.25 kg/ha (1.3 kg/acre) per application.
  • Do not apply on sandy, loamy sandy or gravelly soils with less than 1% organic matter.
  • Do not enter treated area for 12 hours.

Roundup Ultra

(glyphosate)
 
Group 9
0.83 to 1.67 L/ha
(330 to 680 mL/acre)
7
  • Apply in spring before emergence of crop shoots.
  • Fall-seeded rye grass can be ‘burned’ down in the spring before fertilizer is applied.
  • Do not make more than 1 application per year.
  • Do not re-enter treated area for 12 hours.

Roundup WeatherMax

(glyphosate)
 
Group 9
0.83 to 1.67 L/ha
(330 to 680 mL/acre)

7

 

  • Apply in spring before emergence of crop shoots.
  • Fall-seeded rye grass can be ‘burned’ down in the spring before fertilizer is applied.
  • Do not make more than 1 application per year.
  • Do not re-enter treated area for 12 hours.

Credit 45

(glyphosate)
 
Group 9
1.0 to 2.0 L/ha
(400 to 800 mL/acre)
7
  • Apply in spring before emergence of crop shoots.
  • Fall-seeded rye grass can be ‘burned’ down in the spring before fertilizer is applied.
  • Do not make more than 1 application per year.
  • Do not enter treated area within 12 hours of application.

Command 360 ME

(clomazone)

Group 11

Coarse-textured soils: 1.55 L/ha (0.63 L/acre)

Medium-textured soils: 1.95 L/ha (0.80 L/acre)
 
Fine-textured soils:  2.35 L/ha (0.95 L/acre)
14
  • Apply prior to weed and spear emergence.
  • If spears have emerged, apply after a clean harvest, after covering exposed plants with soil prior ot application.
  • Do not apply more than once per season.
  • Controls lamb's quarters, lady's thumb, Eastern black nightshade, barnyard grass and green foxtail. 
  • Controls yellow foxtail at the high rate only.
  • Suppression only of redroot pigweed.
  • Do not incorporate.
  • Do not enter treated area for 12 hours.

Chateau

(flumioxazin)

Group 14
Coarse-textured soils: 280 g/ha (115 g/acre)

Medium-textured soils: 420 g/ha (170 g/acre)
N/A
  • Apply prior to weed emergence.
  • Apply only to dormant asparagus established for at least one year.
  • Apply once per growing season.
  • Do not apply on soils with >5% organic matter.
  • Do not apply to fine-textured soils.
  • To prevent crop injury, ensure an irrigation or rain event occurs between applicaton and spear emergence.
  • Controls redroot pigweed, lamb’s quarters, hairy nightshade, dandelion and black nightshade.

Authority 480

(sulfentrazone)
 
Group 14

0.292 L/ha (0.118 L/acre)

Apply in 100 to 400 L/ha (40 to 160 L/acre) of water at 175 kPa

14
  • Apply as a broadcast in the spring before the crop and weeds emerge.
  • Authority 480 requires adequate rainfall or irrigation to activate.
  • A shallow incorporation may be necessary if irrigation is not available or if rainfall has not provided activation.
  • Do not use on coarse-textured soils classified as sand that have less than 1% organic matter.
  • Do not use on fine-textured soils with less than 1.5% organic matter.
  • Do not apply on soils with an organic matter content greater than 6%.
  • Do not use on soils with a pH of 7.8 or greater.
  • Do not enter treated area for 12 hours.
  • Observe a plantback interval of 24 months for sweet corn and 16 months for winter wheat.
  • Controls redroot pigweed, lamb's quarters, Eastern black nightshade and common groundsel.

Devrinol 50 DF

(napropamide)

Group 15

Tank mixed with:
 

Princep Nine-T

(simazine)

Group 5

9.0 to 13.4 kg/ha (3.6 to 5.4 kg/acre)



 

 

Plus


1.5 to 2.75 kg/ha (0.6 to 1.1 kg/acre)

6
  • Apply in spring to established fields prior to spear emergence.
  • Make only one application per season.
  • Do not apply to soils with more than 10% organic matter
  • Apply in 150 to 300 L/ha (60 to 120 L/acre) of water.
  • Observe a 12 month plant back restriction on crops not listed.

Devrinol 2-XT

(napropamide)

Group 15

Tank mixed with:
 

Princep Nine-T

(simazine)

Group 5

18.75 to 27.92 L/ha (7.59 to 11.30 L/acre)



 

 

Plus


1.5 to 2.75 kg/ha (0.6 to 1.1 kg/acre)

6
  • Apply in spring to established fields prior to spear emergence.
  • Make only one application per season.
  • Do not apply to soils with more than 10% organic matter
  • Apply in 150 to 300 L/ha (60 to 120 L/acre) of water.
  • Observe a 12 month plant back restriction on crops not listed.

Dual II Magnum

(S-metachlor)

Group 15
1.55 to 1.75 L/ha (0.65 to 0.7 L/acre)

Apply in at least 150 L/ha (60L/acre) of water at 200 to 300 kPa
16
  • In the spring, apply to dormant asparagus beds prior to spear emergence or post-harvest.
  • When using post-harvest, apply after the last cut and before fern regrowth occurs.
  • Controls nightshade, barnyard grass, foxtail & suppresses redroot pigweed.
  • Do not tank mix with fluid fertilizers, oils, oil concentrates or surfactants.
  • Rain is required within 10 days of application, or a shallow cultivation.
  • Do not apply to soils with less than 1% or more than 10% organic matter.
  • Make only one application per year.
  • Do not enter treated areas for 12 hours.

Callisto

(mesotrione)

Group 27

300 mL/ha (120 mL/acre)

Apply in 100 to 200 L/ha (40 to 80 L/acre) of water at 206 to 300 kPa

N/A
  • Apply after fern mowing, discing, or other tillage operation but prior to spear emergence.
  • Controls lamb's quarters, redroot pigweed and wild mustard.
  • Can be applied by broadcast or banded application.
  • For banded application, the application must be made to account for band width to deliver the desired rate per hectare.
  • Do not apply more than once per season.
  • If weeds are emerged, use with Agral 90 (0.2% v/v).
  • Do not enter treated area for 12 hours.

Note: for dryland asparagus growers: Residual herbicides such as linuron and simazine require irrigation or rain within 4 to 7 days of treatment to activate them.

*PHI = Pre-harvest interval
BUFFERS – Refer to product label for buffer requirements, and consult the Vegetable Production Guide: Pesticide Regulations and Safety (PDF).
PESTICIDE GROUP DETAILS – see the Vegetable Production Guide: Pesticide Toxicity Table (PDF).

After Last Cutting: Herbicide Application Rates

Product Rate PHI* Comments

Excel Super

(fenoxaprop-p-ethyl)

Group 1

670 mL/ha (270 mL/acre)

Apply in at least 110 L/ha (45 L/acre) of water at 275 kPa
N/A
  • Apply when weeds are at the 1 to 6 leaf stage.
  • Controls green and yellow foxtail, barnyard grass, crabgrass, fall panicum, Proso millet and old witch grass.
  • Does not control quackgrass, sedges or other perennial grasses.
  • Apply after harvest only.
  • Do not apply any other pesticides or chemicals 4 days before or after applying Excel Super.
  • Do not spray the asparagus fern.

Sandea

(halosulfuron)

Group 2

35 to 105 g/ha (14.2 to 42.5 g/acre)

Apply in 140 L/ha (57 L/acre) of water
1
  • Apply on actively growing weeds at the heights defined in the "USE RATE GUIDE" section of the label. 
  • See "Seed-bed Asparagus" table o fthis guide for labelled weeds.
  • For heavy yellow nutsedge infestations, split applications should be made.
  • To minimize crop injury and for more effective control, apply using drop nozzles directing the spray below the fern.
  • May cause temporary yellowing of the fern.
  • A nonionic surfactant or crop oil concentrate should be used with post-harvest applications.
  •  A sequential application may be necessary for some annual and perennial weeds.
  • Do not apply more than two times per season.
  • Repeat application at a 21 day interval.
  • Do not re-enter treated area for 12 hours.
  • Do not use more than 140 g/ha (57 g/acre) of product per season.

Ignite 15 SN

(glufosinate ammonium)

Group 10

2.7 to 5.0 L/ha (1.1 to 2.0 L/acre)

Apply in 110 to 330 L/ha (45 to 135 L/acre) of water at 275 to 310 kPa.
N/A
  • Apply after spears have been harvested.
  • Rainfall within 4 hours of application may reduce effectiveness.
  • Do not handle with bare hands or with leather or cloth gloves.
  • Do not use pre-plant or pre-emergence on sandy soils lacking clay minerals.

*PHI = Pre-harvest interval
BUFFERS – Refer to product label for buffer requirements, and consult the Vegetable Production Guide: Pesticide Regulations and Safety (PDF).
PESTICIDE GROUP DETAILS – see the Vegetable Production Guide: Pesticide Toxicity Table (PDF).

 

Asparagus Insect Management

 

Bees are attracted to asparagus bloom. Where spraying is being done, bee poisoning may result. Sevin is especially toxic to bees and should not be used during the bloom period.

With other insecticides, losses to bees can be reduced if sprays are applied in early morning or late evening when the bees are not foraging. Advise local beekeepers of spraying activity.

Small, green, soft-bodied, sap-sucking insects up to 1.5 mm in length. Usually found feeding at base of leaves and on the small branches.

Aphid infested plants develop “witches’ broom” type growth and produce numerous thin spears. Infestations which occur as spears are opening produce the most severe growth distortion and fern damage. Roots and crowns are also damaged from above-ground aphid feeding. Crowns surviving infestations produce only a few late, weak spears the following spring.

Currently, this pest is found only in the Okanagan and Similkameen Valleys as far north as Armstrong and Spences Bridge, and in the Grand Forks area.

Control

  • Destroy or burn old fern growth to control the overwintering eggs.
  • Spray after harvest when spears are developing into fern growth (see table below).
  • Apply the insecticides in enough water to cover and penetrate fern growth. Do not spray to the point of run-off.

Chemical Control of Asparagus Aphid

Product Rate PHI* Comments

Cygon 480/ Lagon 480 E

(dimethoate)

Group 1B
2.3 L/ha 
(930 mL/acre)

Apply in 675 L/ha (275 L/acre) of water
N/A
  • Apply as a groundspray using a closed cab.
  • For mature asparagus, begin applications in July, after crop is harvested and continue at 3 to 4 week intervals until defoliation in October.
  • Do not apply more than 2 times per season.
  • For immature asparagus, begin applications mid-May.
  • Repeat using a 7 day interval.
  • Note:  dimethoate should be applied postharvest only; but if applied on immature asparagus - do not harvest for feed or food.
  • Toxic to bees.  Do not apply during the crop blooming period or during the 5 day period before the crop blooms.
  • Do not re-enter treated area for 12 hours.

Matador 120 EC

(lambda-cyhalothrin)

Group 3
83 mL per ha
(34 mL per acre)

Apply in 100 to 200 L/ ha (40 to 80 L per acre) of water
N/A
  • Apply post-harvest to ferns only.
  • Apply at 7 to 10 day intervals.
  • This product is very toxic to bees. Avoid spraying when bees are foraging.
  • Do not apply more than 3 times per season.
  • Do not enter treated area for 24 hours.

Assail 70WP

(acetamiprid)

Group 4
56 to 86 g/ha
(22 to 34 g/acre)

Apply in 190 L/ha (77 L/acre) of water.
1
  • Apply to new plantings and when plants are young.
  • Repeat at a 10 day interval.
  • Maximum 2 applications per season.
  • Do not apply more than 320 g/ha (130 g/acre) per growing season.
  • Toxic to bees.
  • Do not re-enter treated area for 12 hours.
 
*PHI = Pre-harvest interval.
BUFFERS – Refer to product label for buffer requirements, and consult the Vegetable Production Guide: Pesticide Regulations and Safety (PDF).
PESTICIDE GROUP DETAILS – see the Vegetable Production Guide: Pesticide Toxicity Table (PDF).
OMRI-USA = Organic Materials Review Institute of USA

Beetles are 6 mm long with dark-blue wing covers. Each wing cover has three large square cream spots. Larvae are dark gray, fleshy with black heads, and about 8 mm long when full grown. Beetles feed on developing spears during the cutting season. Later, beetles and larvae feed on frond growth.

Control

  • Remove asparagus volunteers, and burn or bury plant refuse in the fall to reduce insect populations.
  • Spray as beetles appear, with one of the products listed in the table below.

Chemical Control of Asparagus Beetle or Spotted Asparagus Beetle

Product Rate PHI* Comments

Sevin XLR

(carbaryl)

Group 1A
2.5 to 6.4 L/ha 
(1.0 to 2.6 L/acre)
2
  • Maximum of 2 applications per year.
  • Repeat at 7 day interval.
  • Use lower rate on young plants.
  • Toxic to bees.  Do not apply during the crop blooming period.
  • Do not enter treated area for irrigation activities for 6 days.  Do not re-enter for hand-weeding for 12 hours.

Malathion 85E

(malathion)

Group 1B
1220 mLha 
(495 mL/acre)

Apply in 1000 L/ha (405 L/acre) of water
1
  • Do not make more than 1 application per year.
  • Best control is obtained when the temperature is above 20°C.
  • Toxic to fish.
  • Do not apply where runoff is likely to occur.
  • Do not apply after expiry date on the container label.
  • Do not re-enter treated area for 12 hours.

Mako

(cypermethrin)
 
Group 3
86 mL/ha
(35 mL/acre)
 
Apply in 100 to 500 L/ha (40 to 200 L/acre) of water.
1
  • Apply to spears or ferns.
  • Repeat using 7 day intervals.
  • Do not make more than 3 applications per year.
  • Very toxic to bees. Avoid spraying when bees are foraging.
  • Do not re-enter treated area for 12 hours.

Up-Cyde 2.5 EC

(cypermethrin)
 
Group 3
140 mL//ha
(60 mL/acre)
 
Apply in 100 to 500 L/ha (40 to 200 L/acre) of water
1
  • Repeat using 7 day intervals.
  • Do not apply more than 3 times per year. 
  • Apply to spears or ferns.
  • Very toxic to bees. Avoid spraying when bees are foraging.
  • Do not re-enter treated area for 12 hours.

Decis 5 EC

(deltamethrin)

Group 3
200 mL/ha
(80 mL/acre)

Apply in 200 to 500 L/ha (80 to 200 L/acre) of water
N/A
  • Apply after harvest period only, prior to egg laying.
  • Repeat as needed.
  • Repeat at 3 week intervals or as required.
  • Toxic to bees and beneficial insects.

Assail 70WP

(acetamiprid)

Group 4
80 to 160 g/ha
(32 to 65 g/acre)

Apply in 190 L/ha (77 L/acre) of water.
1
  • Repeat using a 10 day interval.
  • Maximum 2 applications per season.
  • Do not apply more than 320 g/ha (130 g/acre) per growing season.
  • Toxic to bees.
  • Do not re-enter treated area for 12 hours.

Delegate WG

(spinetoram)

Group 5
140 to 280 g/ha
(60 to 115 g/acre)
140 to 280 g/ha
(60 to 115 g/acre)
60
  • Suppression only.
  • Apply to the ferns only.
  • Maximum of 3 applications per year.
  • Toxic to bees. Avoid spraying when bees are foraging.
  • Do not apply more often than once every 5 days.
  • Do not enter treated area for 12 hours.

Entrust 80

(spinosad)
 
Group 5
 
Used in organics
88 g/ha
(36 g/acre)
60
  • Apply post-harvest to the ferns.
  • Repeat at 7 to 10 day intervals.
  • Do not apply more than 3 times per year.
  • Highly toxic to bees.  Do not apply if bees are visiting the area.  
  • Harmful to parasitoids and predatory mites.  Slightly harmful to foliage-dwelling predators.
  • Entrust products are OMRI-USA listed.  Check with your certification body before using in an organic operation.
  • Do not re-enter treated area until residues have dried.

Entrust

(spinosad)
 
Group 5
 
Used in organics
294 mL/ha
(119 mL/acre)
60
  • Apply post-harvest to the ferns.
  • Repeat at 7 to 10 day intervals.
  • Do not apply more than 3 times per year.
  • Highly toxic to bees.  Do not apply if bees are visiting the area.  
  • Harmful to parasitoids and predatory mites.  Slightly harmful to foliage-dwelling predators.
  • Entrust products are OMRI-USA listed.  Check with your certification body before using in an organic operation.
  • Do not re-enter treated area until residues have dried.

Success

(spinsosad)
 
Group 5
145 mL/ha
(59 mL/acre)
60
  • Repeat at 7 to 10 day intervals.
  • Do not apply more than 3 times per year.
  • Highly toxic to bees.  Do not apply if bees are visiting the area.  
  • Harmful to parasitoids and predatory mites.  Slightly harmful to foliage-dwelling predators.
  • Do not enter treated area until residues have dried.
 
*PHI = Pre-harvest interval.
BUFFERS – Refer to product label for buffer requirements, and consult the Vegetable Production Guide: Pesticide Regulations and Safety (PDF).
PESTICIDE GROUP DETAILS – see the Vegetable Production Guide: Pesticide Toxicity Table (PDF).
OMRI-USA = Organic Materials Review Institute of USA

Cutworms are drab, fat caterpillars measuring up to 5 cm long which curl up when disturbed. They chew holes in emerging spears above or below ground level, often causing distortion of spears.

Control

Chemical Control of Cutworms

Product Rate PHI* Comments

Sevin XLR

(carbaryl)

Group 1A
2.5 to 6.4 L/ha
(1.0 to 2.6 L/acre)
2
  • Use sufficient water to wet the soil around the base of each plant.
  • Use lower rate on young plants
  • Sprays should be applied on a warm evening.
  • Do not apply more often than once every 3 days.

Pounce EC/ Perm-Up EC

(permethrin)

Group 3
180 to 390 mL/ha
(75 to 160 mL/acre)
2
  • Application should be made under warm, moist conditions in the evening.
  • Use the higher rate under dry soil conditions or where cutworms are large (2.5 to 4 cm long).
  • Do not disturb the soil surface for 5 days after treatment.
  • Use 180 mL/ha (75 mL/acre) for seedlings or transplant application.
  • A single application of 180 mL/ha (75 mL/acre) can be made during cutting season.
  • Very toxic to bees. Avoid spraying when bees are foraging.
*PHI = Pre-harvest interval.
BUFFERS – Refer to product label for buffer requirements, and consult the Vegetable Production Guide: Pesticide Regulations and Safety (PDF).
PESTICIDE GROUP DETAILS – see the Vegetable Production Guide: Pesticide Toxicity Table (PDF).
OMRI-USA = Organic Materials Review Institute of USA
 

Thrips are very small (1 mm) yellowish to brown winged insects which suck plant juices. Asparagus for canning must be free of thrips.

Control

Good weed control during the cutting season in asparagus and adjacent fields will minimize thrips infestations. Insecticides are not usually necessary.

Winged (adult) grasshoppers migrate into plantings during July and August and feed on the green outer layer of ferns and on small branches and leaves.

Control

When migrations begin, spray headlands and borders of planting to intercept moving grasshoppers. Spot treat areas within fields where damage appears. Use products as listed in the Vegetable Production Guide: Pest Management (PDF, 1.2 MB).

 

Asparagus Disease Management

Three different viruses can contribute to stand decline in asparagus. They are asparagus viruses I and II (AV-I, AV-II) and tobacco streak virus (TSV). Tobacco streak virus causes stunting and small spears. AV-I and AV-II reduce yield individually and when both are present, cause the plant to die within 2 – 3 years. AV- I is spread by various aphids but not by the asparagus aphid. AV-II is seed-borne and probably pollen-borne. Little is known about the spread of TSV in asparagus.

Control

When starting a new field in an isolated area use only seed tested and found free of AV-II.

Growing spears are stunted, yellow and may wilt. Fern growth is also yellow and stunted. Crowns, roots and stems may show discolouring of vascular bundles and varying amounts of decay.

Control

  • If possible grow your own crowns on well-drained land that has never grown asparagus.
  • Treat seed for two hours in a solution of 1 L household bleach in 5 L of water. Lift and shake periodically.
  • Avoid planting production crops in fields known to be infested; in fields which have grown asparagus within five years; or in fields with undecomposed corn residue.
  • Minimizing plant stress through good cultural procedures will reduce damage from Fusarium.
  • Do not plant asparagus following corn which is a host for some Fusarium species that attack asparagus.

Rust is most serious in wet seasons on stems and leaves. It causes elongated, orange-red, powdery pustules which turn black in the fall. Warm weather (10 - 30 °C) with heavy dew, fog or light rains enhances rust development. The disease is spread via wind-blown spores.

Control

  • Avoid establishing new plantings close to old, established crops.
  • Destroy volunteers within 300 m.
  • For new plantings which are not being harvested, begin a spray program when the top growth is about 30 cm high. For producing fields, begin spray program after harvest has been completed for the year but before the disease appears. See table below.
  • In areas where it is permitted, burn the stubble late in the fall while it is still dry. If that is not possible, the stubble must be shredded and disced into the soil before spear emergence in the spring.
  • While all varieties are susceptible to infection, they differ in the rate of rusting and consequently in the amount of dam.

Chemical Control of Rust

Product Rate PHI* Comments

Bravo 500


(chlorothalonil)

Group M
3.4 L/ha (1.4 L/acre)

Apply in at least 100 to 200 L/ha (40 to 80 L/acre) water
190
  • Begin applications following final harvest of spears.
  • Apply at 14 day intervals.
  • Do not apply more than 3 times in a season.
  • Do not enter treated areas for 48 hours

Nova 40W


(myclobutanil)

Group 3
340 g/ha (138 g/acre)

Apply in 370 L/ha (150 L/acre) of water
N/A
  • Use as a post-harvest treatment of ferns.
  • Repeat at 7 day intervals.
  • Do not apply more than 5 times per season.
  • Do not enter treated areas until spray has dried.

Polyram DF


(metiram)

Group M
2.25 to 3.25 kg/ha (0.9 to 1.3 kg/acre) N/A
  • Do not make more than 4 applications/year.
  • Apply at 7 to 10 day intervals.
  • Apply after harvest only.

Flint

 

(trifloxystrobin)

Group 11

210 to 280 g/ha (85 t0 115 g/acre)

Apply in 280 L/ha (115 L/acre) of water at 241.5 kPa

180
  • Repeat at 7 to 14 day intervals.
  • Make applications to the fern stage only.
  • Mow down ferns or allow ferns to senesce between the last application and harvest.
  • Do not apply more than 840 g/ha (340 g/acre) of product per season.
  • Do not make more than 3 applications or other strobilurin (Group 11) fungicide per season.
  • Do not re-enter treated area for 12 hours.
  • Do not use in greenhouses.
  • Harmful to beneficial predatory or parasitic arthropods.

*PHI = Pre-harvest interval
BUFFERS – Refer to product label for buffer requirements, and consult the Vegetable Production Guide: Pesticide Regulations and Safety (PDF).
PESTICIDE GROUP DETAILS – see the Vegetable Production Guide: Pesticide Toxicity Table (PDF).

Small purple spots which may join to form elongated lesions appear on spears in the spring. Injury is usually worse during cool, wet conditions when spear growth is slow. Lesions often occur on one side causing the spear to twist and curl rendering it unmarketable.

Control

  • Avoid introducing the disease by using treated seed (as recommended under Fusarium above) or crowns from a disease-free field.
  • Burn all old fern growth at the end of the season, or shred it and disc it into the soil prior to spear emergence in the spring.
  • On sandy soils, it has been shown that measures such as seeding cover crops and then killing them in the spring will reduce sand-blasting and infection of the emerging spears.
  • There are no fungicides registered for spring application to emerging spears.

Chemical Control of Purple Spot

Product Rate PHI* Comments

Bravo 500

(chlorothalonil)

Group M
3.4 L/ha (1.4 L/acre)

Apply in 100 to 200 L/ha (40 to 80 L/acre) water
190
  • Begin applications following final harvest of spears.
  • Apply at 14 day intervals.
  • Do not apply more than 3 times in a season.
  • Do not enter treated areas for 48 hours

Quadris


(azoxystrobin)

Group 11
453 to 1124 mL/ha (183 to 455 mL/acre)

Apply in 100 L/ha (40 L/acre) of water
180
  • Begin applications after final harvest of spears, prior to disease development.
  • Apply at 7 to 14 day intervals.
  • Do not apply more than 3 times per crop season.
  • Do not re-enter treated area until residues have dried.

Flint

 

(trifloxystrobin)

Group 11

210 to 280 g/ha (85 t0 115 g/acre)

Apply in 280 L/ha (115 L/acre) of water at 241.5 kPa

180
  • Repeat at 7 to 14 day intervals.
  • Make applications to the fern stage only.
  • Mow down ferns or allow ferns to senesce between the last application and harvest.
  • Do not apply more than 840 g/ha (340 g/acre) of product per season.
  • Do not make more than 3 applications or other strobilurin (Group 11) fungicide per season.
  • Do not re-enter treated area for 12 hours.
  • Do not use in greenhouses.
  • Harmful to beneficial predatory or parasitic arthropods.

*PHI = Pre-harvest interval
BUFFERS – Refer to product label for buffer requirements, and consult the Vegetable Production Guide: Pesticide Regulations and Safety (PDF).
PESTICIDE GROUP DETAILS – see the Vegetable Production Guide: Pesticide Toxicity Table (PDF).