Garlic

Last updated on June 28, 2024

Garlic

Growing Garlic

 

Varieties

There are many types, varieties and selections of garlic. Some of the most commonly grown include Spanish Roja, Yugoslavian and French. California Early and California Late are also grown, but markets seem to prefer pungent types compared to mild.

Roadside and specialty markets prefer selections having pink, red or purple streaks in the skin. Supermarkets generally prefer white skin garlic.

Elephant garlic is not a true garlic. It is more closely related to leeks.

 

Soils

Garlic can be grown on a wide range of soil types if they are well-drained, deep and fertile. Soils with good organic matter are preferred due to increased moisture and nutrient holding capacity. Extremely heavy soils should be avoided. Soil pH should range from 6.0 - 7.5.

 

Seed Sources

Garlic planting stock can carry viruses, white rot, and bulb and stem nematode. If these problems are brought in, land can be made unusable for the production of garlic and related crops such as onions. Make every effort to obtain planting stock from a reliable, disease-free source.

 

Seeding

Cultivated garlic does not produce true seed. All garlic is propagated vegetatively by separating the bulbs into individual cloves either by hand or by machine (cracking). Hand separation is much less damaging to the cloves.

Seeding rate is about 700 to 1000 kg/ha (280 to 400 kg/acre) of garlic cloves. Depth of planting is 3 to 5 cm. Row spacing is 7 to 12 cm apart within the row and at least 20 cm between rows depending on methods of weed control to be used. Garlic can be planted in single rows or in multi-row beds. Beds may be raised or on the flat.

Seeding Date

In the Southern Interior, garlic is planted in the fall from September to mid-October. In the South Coastal Region and perhaps North Central areas, spring planting is sometimes preferred, but planting must be done as early as soil and weather conditions allow.

 

Irrigation

Garlic is shallow-rooted and is sensitive to moisture stress. For most soil types, approximately 2.5 cm of water is required per week. On very dry, sandy soils, as much as 5.0 cm is required weekly. Irrigation should not be applied within two weeks of harvest.

 

Fertilizer

A soil test is required to determine nutrient requirements. Phosphorus and potassium requirements are similar to onions. Use the Vegetable Production Guide: Nutrient Management (PDF) for recommendations based on soil test results.

Note: Commercial garlic can be grown conventionally using chemical fertilizers or organically using composted manure or other materials.

 

Harvesting

Garlic is ready for harvesting when the tops begin to turn yellow. If harvest is delayed, wrapper scales that hold the cloves together will deteriorate and the bulbs may shatter. Digging is done by hand or with a tractor-mounted cutter bar that cuts the roots and lifts the bulbs. The plants are tied into bundles. Dirt may be washed from the bulbs, but this will result in a need for additional curing.

 

Curing

The bundles are placed on racks in an unheated building. This method is slow, so many growers increase air movement with fans to shorten the curing period. Curing is followed by cleaning, root trimming, sorting, grading, (braiding) and storage.

 

Garlic Weed Management

Garlic competes poorly with weeds. Cultivation should be frequent and shallow to avoid root damage. A straw mulch 4 inches thick can effectively suppress weeds. See tables below for herbicide recommendations.

 

Pre-emergence

Pre-emergence: Herbicide Application Rates

Product Rate PHI* Comments

Chateau

(flumioxazin)

Group 14
Coarse textured soils
(<5% organic matter):
280 g/ha
(113 g/acre)

Medium textured soil
(<5% organic matter):
420 g/ha
(170 g/acre)
N/A
  • Controls redroot pigweed, lamb’s quarter, Eastern nightshade and dandelion.
  • Apply prior to emergence of weeds.
  • Apply prior to emergence of garlic and within 3 days of planting garlic.
  • Apply only once during the growing season.
  • Do not apply on soils with >5% OM, or fine-textured soils.
  • Control may be improved by irrigation with at least ½ cm of water.
  • Weed control will be reduced if there is mechanical incorporation into the soil or if emerged weeds are controlled by cultivation.
  • Applications made to poorly drained soils or under cool, wet conditions may result in crop injury.
  • Observe a 12 month plantback interval for crops not listed.  See Rotational Restrictions table of label.
  • Do not enter treated area for 12 hours.

Devrinol 50-DF

(napropamide)

Group 15

2.24 to 4.5 kg/ha
(0.9 to 1.8 kg/acre)

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

N/A
  •  Apply once per season.
  •  Controls a variety of annual grasses and broadleaf weeds.
  •  Use lower rate on sand and sandy loam soils.
  •  Not recommended for use on soils with over 10% organic matter.
  •  All weed growth and crop stubble must be thoroughly worked into the soil before planting.
  •  There is a 12 month plant back restriction for crops not on the label.
  •  Do not enter treated area for 12 hours.

Devrinol 2-XT

(napropamide)

Group 15

4.67 to 9.38 L/ha
(01.90 to 3.80 L/acre)

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

N/A
  •  Apply once per season.
  •  Controls a variety of annual grasses and broadleaf weeds.
  •  Use lower rate on sand and sandy loam soils.
  •  Not recommended for use on soils with over 10% organic matter.
  •  All weed growth and crop stubble must be thoroughly worked into the soil before planting.
  •  There is a 12 month plant back restriction for crops not 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).

 

Post-emergence

Post-emergence: Herbicide Application Rates

Product Rate PHI* Comments

Poast Ultra

(sethoxydim)

Group 1

Note:  No longer produced

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)

50
  • 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).
  • Annual bluegrass is not controlled.
  •  Apply when annual weeds are in the 1 to 6 leaf stage and when quackgrass is in the 1 to 3 leaf stage.
  •  Apply in 50 to 200 L/ha (20 to 80 L/acre) of water at 240 kPa pressure..
  •  See label for water volume and pressure when weed infestations or crop canopies are dense.
  • Observe a 30 day plantback interval for crops not listed.
  • Do not enter treated area for 12 hours.

Venture L

(fluazifop-P-butyl & S-isomer)

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)

42
 

 

42
 

 

42
 

 

60
  • Annual bluegrass and broadleaved weeds are not controlled.
  • If 1.0 L/ha (400 mL/acre) or less is used, one repeat application may be applied.
  • At the higher rates only one application is permitted per season.
  • Apply in 50 to 200 L/ha (20 to 80 L/acre) water at 200 to 300 kPa.
  • Apply using 425 kPa pressure for dense weed infestations or dense crop canopies.
  • 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.
  • Observe a plantback interval of 12 months for crops not listed.
  • Do not re-enter treated area for 12 hours.

Centurion/Select

(clethodim)

Group 1

0.19 to 0.38 L/ha
(77 to 154 mL/acre

Apply in 55 to 225 L/ha (22 to 90 L/acre) of water at 275 kPa
45
  • Do not apply more than 1 time per season.
  • Do not apply more than 0.38 L/ha (154 mL/acre) per season.
  • Apply when onions are in the 1 to 4 leaf stage.
  • Use with the adjuvant Amigo at 0.5 to 1.0% v/v.
  • See label for rates depending on weed types and weed-leaf growth stages.
  • Controls annual grasses and suppresses quack grass.
  • Allow 4 days between this application and any other chemical not found on the label.
  • Do not enter treated area for 12 hours.

Prowl H2O

(pendimethalin)

Group 3

Mineral soils:

2.42 L/ha
(0.98 L/acre)

Muck soils:

6.6 L/ha
(2.7 L/acre).

Apply in 250 L/ha (100 L/acre) of water

45
  • Destroy existing weeds before applying.
  • Apply after the crop has emerged, up to the 4 true-leaf stage of garlic growth.
  • Rainfall or irrigation within 7 days of application improves control.
  • Do not feed treated crop to livestock.
  • See label for rotational crops and plantback restrictions.

Mineral soils:

  • Controls redroot pigweed and lamb's-quarters.
  • Do not apply more than one time per year.
  • Do not re-enter treated area for 24 hours.

Muck soils:

  • Controls grass and annual weeds including barnyard grass, chickweed, lamb's-quarters and pigweed.
  • To avoid crop injury, ensure good soil coverage during planting.
  • For season-long control, make a second application using a 3 week interval.
  • Do not apply more than twice per year.
  • Should weeds develop, a shallow cultivation or rotary hoeing will generally result in better weed control.
  • Do not re-enter treated area for 5 days for scouting or thinning.

Pardner

(bromoxynil)

Group 6

1.0 L/ha
(400 mL/acre)
58
  • Apply early post-emergence.
  • Apply only once per season.
  • To the four leaf stage: controls green and pale smartweed, lady’s thumb, wild mustard, kochia, cow cockle, Russian thistle, stinkweed, cocklebur, common ragweed, pigweed, velvet leaf, bluebur and American nightshade.
  • To the eight leaf stage: controls wild, tartary and common buckwheat, common groundsel and lamb’s quarters.

Bromotril 240 EC

(bromoxynil)

Group 6

1.2 L/ha
(480 mL/acre)

Apply in 200 to 300 L/ha (80 to 120 L/acre) of water at 275 kPa
58
  • Apply early post-emergence.
  • Apply only once per season.
  • To the four leaf stage: controls green and pale smartweed, lady’s thumb, wild mustard, kochia, cow cockle, Russian thistle, stinkweed, cocklebur, common ragweed, pigweed, velvet leaf, bluebur and American nightshade.
  • To the eight leaf stage: controls wild, tartary and common buckwheat, common groundsel and lamb’s quarters.

Aim EC

(carfentrazone-ethyl)

Group 14

37 to 117 mL/ha
(15 to 47 mL/acre)

Apply in 100 L/ha (40 L/acre) of water
1
  • Controls annual weeds.
  • Must be applied using hooded sprayers to weeds between the rows of the emerged crop.
  •  Use an adjuvant such as Agral 90 or Agral-Surf at 0.25% v/v (0.25 L/100 L of spray solution) or Merge at 1% v/v (1 L/100 L of spray solution).
  • Precaution:  crop injury will occur when spray drift is allowed to come in contact with green stem tissue or leaves.
  • Apply only once per growing season.

*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).

 

Garlic Insect Management

 

Onion Maggots

Small, grayish fly, smaller than a house fly, lays eggs at base of plants. Small, white maggots feed in onion bulbs. If attack occurs early, plants may be killed. If attacked later, plants live, but the bulbs are misshapen and contain maggots. Secondary rot often occurs.

Maggots have not been a significant problem in garlic production to date.

Monitoring

Monitoring with white sticky traps is useful to detect both onion maggot flies and onion thrips. With this information, control can be achieved with fewer sprays. Onion flies, however, cannot be properly identified without the use of a dissecting microscope and considerable expertise. Commercial scouting services are recommended for accurate identification.

Control

Cull piles should be removed to the dump or buried to prevent onion fly breeding and subsequent field infestation.

 

Thrips

Very tiny (1 mm), black, brown or yellow insects cause silvering and speckling of leaves. If severe, yield may be affected.

Control

Use one of the products listed in the table below.

Chemical Control of Thrips

Product Rate PHI* Comments

Malathion 85E

(malathion)

Group 1B
535 to 1345 mL/ha
(215 to 545 mL/acre)
 
Apply in 1000 L/ha (405 L/acre) of water
3
  • Do not make more than one application per year.
  • Best control 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.

Delegate WG

(spinetoram)

Group 5

200 to 336 g/ha
(81 to 136 g/acre)

Apply in 300 to 500 L/ha (120 to 200 L/acre) of water

3
  • Suppression only.
  • For optimal performance, final solution pH should be in the range of 6 to 8.
  • Apply at egg hatch or to small larvae.
  • Ensure spray solution penetrates to leaf axils.
  • Repeat at 7 to 10 day intervals.
  • Maximum of 3 applications per year.
  • Toxic to bees. Avoid spraying when bees are foraging.
  • Do not re-enter treated area for 12 hours.

Movento 240 SC

(spirotetramat)

Group 23

365 mL/ha
(150 mL/acre)

Apply in 200 L/ha (80 L/acre) of water
3
  • Controls larvae.
  • Repeat at 7 day intervals.
  • Do not apply more than twice per season.
  • Maximum allowed per crop season: 730 mL/ha (295 mL/acre).
  • Movento 240 SC should be used with one of the following adjuvants: non-ionic (eg. Agral 90 or Ag-Surf) or methylated seed oil (eg. Hasten).
  • Reduction in numbers of thrips larvae may take 3 to 4 days after application.
  • Do not enter treated area for 12 hours.
  • Toxic to bees.  Do not apply when flowering weeds are present.

Entrust 80

(spinosad)
 
Group 5
 
Used in organics

131 to 158 g/ha
(53 to 64 g/acre)

Apply in 300 to 500 L/ha (120 to 200 L/acre) of water.

3
  • Suppression only.
  • Apply when onion thrips first appear targeting egg hatch or small nymphs.
  • Repeat at 7 to 10 day intervals.
  • Do not apply more than three times per season.
  • 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

437 to 527 mL/ha (177 to 213 mL/acre)

Apply in 300 to 500 L/ha (120 to 200 L/acre) of water.

3
  • Suppression only.
  • Apply when onion thrips first appear targeting egg hatch or small nymphs.
  • Repeat at 7 to 10 day intervals.
  • Do not apply more than three times per season.
  • 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

(spinosad)
 
Group 5

218 to 262 mL/ha
(88 to 106 mL/acre)

Apply in 300 to 500 L/ha (120 to 200 L/acre) of water.

3
  • Suppression only.
  • Apply when onion thrips first appear targeting egg hatch or small nymphs.
  • Repeat at 7 to 10 day intervals.
  • Do not apply more than three times per season.
  • 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.

Agri-Mek 1.9% EC

(abamectin)
 
Group 6

600 to 1200 mL/ha
(243 to 485 mL/acre)

Apply in 200 L/ha (80 L/acre) of water.

30
  • Apply when onion thrips first appear.
  • Use a non-ionic surfactant at the rate of 0.25 to 0.5% v/v of spray mixture.
  • Repeat at 7 day intervals.
  • Do not apply more than 3 times per season.
  • Highly toxic to bees exposed to direct treatment, drift or residues from blooming plants.
  • Check label for re-entry.

Exirel

(cyantraniliprole)
 
Group 28

1000 to 1500 mL/ha
(405 to 605 mL/acre)

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

1
  • Suppression only.
  • Do not make more than 4 applications per growing season.
  • Repeat at 5 day intervals.
  • Do not apply more than 4.5 L/ha (1.8 L/acre) per season.
  • Use with an adjuvant such as Hasten NT at a rate of 0.25% v/v or MSO Concentrate with Leci-Tech at a rate of 0.5% v/v.
  • Toxic to bees and certain beneficial insects.  Apply early in the morning or late in the evening when bees are not active.
  • Note:  Do not tank-mix or apply in sequence with strobilurin-, copper- or captan-containing fungicides.
  •  Observe a plantback interval of 30 days for legume vegetables, cereals, grass, crop group 1A (including beets, carrots, radish, parsnip, turnip) and crop group 2 (including beet greens and turnip greens). 
  • Observe a plantback interval of 1 year for crops not on this 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).

OMRI-USA = Organic Materials Review Institute of USA

 

Garlic Bulb Mites

Bulb mites are shiny, creamy white, bulbous-appearing mites that range in size from 0.5 to 1.0 mm long. They look like tiny pearls with legs. They are almost always associated with physical damage such as bruising or cutting. They can damage bulbs by penetrating the outer layer of tissue and allowing rotting organisms to enter. Numerous small, raised brown pustules or blisters are seen on the cloves under the skin and sometimes a white, spidery webbing.

Control

Fallow fields to allow the complete decomposition of organic matter. Rotate with non-onion crops. Hot water treatment of seed garlic before planting may reduce mite infestations. Do not use badly infested garlic for seed. Thorough sanitation of areas where bulbs have been stored is recommended.

 

Garlic Disease Management

 

Green Mould (Penicillium)

Affected cloves fail to emerge in the spring or produce weak, stunted plants.

Control

Crack seed immediately before planting. Avoid damaging cloves. Dip cracked cloves for 30 minutes prior to planting in the following suspension:

 

Chemical Control of Green Mould (Penicillium)

Product Rate PHI* Comments

*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).

 

White Rot

(Sclerotium cepivorum)

This disease has been identified in several garlic plantings in the Southern Interior and South Coast. Make every effort to obtain planting stock from a reliable, disease-free source.

This serious disease is now well established in the Southern Interior, Cloverdale and Burnaby onion-growing areas. Infected plants show yellowing and die-back of the leaf tips, progressing downward to the roots. Bulbs develop watery decay, eventually covered with white, fluffy, fungus growth dotted with masses of small black sclerotia.

Control

Once established in a field, white rot builds up whenever onion or garlic is grown. The sclerotia can persist in the soil for 10 years or more. Control is difficult and costly so utmost precautions should be taken to prevent spread into new fields. Avoid growing onions in fields known to be infested if at all possible. Wash down equipment in a safe area when moving from an infested to a clean field. Dispose of diseased onions, trash and containers in such a way as to minimize the chances of contaminating new areas.

Take steps to reduce the danger of flood waters carrying diseased onions and sclerotia from field to field. It is especially important to avoid contaminating clean land with infected transplants or sets which were grown on infested land. See Garlic Disease Management tables in this section.

 

Botrytis Leaf Blight

Chemical Control of Botrytis Leaf Blight

Product Rate PHI* Comments

Serenade Opti

(Bacillus subtilis)
 
Used in organics

1.7 to 2.5 kg/ha
(690 to 1000 g/acre)
0
  • Suppression only.
  • Repeat using a 7 to 10 day interval.
  • Serenade Opti (PCP# 31666) is OMRI-Canada listed.  Check with your certification body before using in an organic operation. 

Cueva

(copper octanoate)
 
Group M1
 
Used in organics
Use a 0.5% to 2% solution at 470 to 940 L/ha (190 to 380 L/acre) 1
  • For a 0.5% solution, mix 1 part Cueva to 200 parts water.
  • For a 2% solution, mix 1 part Cueva to 50 parts water.
  • Repeat at 7 to 10 day intervals.
  • Repeat at 5 to 7 day intervals following heavy rain or when disease pressure is high.
  • Do not make more than 15 applications per year.
  • Time applications so that 12 hours of dry weather follow application.
  • Cueva products (PCP# 31825) are OMRI-Canada listed.  Check with your certification body before using in an organic operation.
  • Do not re-enter treated area for 4 hours.

Sercadis

(fluxapyroxad)
 
Group 7
333 to 666 mL/ha
(135 to 270 mL/acre)

Apply in 100 L/ha (40 L/acre) of water
7
  • Repeat at 7 to 14 day intervals.
  • Do not make more than 3 applications per season.
  • Do not apply more than 2.0 L/ha (809 mL/acre) per season
  • No more than 2 consecutive applications before alternating with a fungicide with a different mode of action.
  • Do not enter treated area for 12 hours.
  • For crops not listed, observe a plant back interval of 1 year.

Scala SC

(pyrimethanil)

Group 9
2.0 L/ha
(800 mL/acre)

Apply in at least 300 L/ha (121 L/acre) of water 
7
  • Repeat using a 7 to 14 day application interval.
  • Maximum application of 6 L/ha (2.4 L/acre) per season.
  • Do not enter treated area for 24 hours for hand thinning or 12 hours for all other activities.

Switch 62.5 WG

(cyprodinil & fludioxonil)

Group 9 & 12
775 to 975 g/ha
(314 to 395 g/acre)

Apply in 200 L/ha (80 L/acre) of water
7
  • Repeat using a 7 to 14 day application interval.
  • Do not make more than 3 applications per year.
  • Observe a 30 day plantback interval for crops not listed.
  • Do not enter treated area for hand weeding for 3 days, and for all other activities do not re-enter for 12 hours.

Acapela

(picoxystrobin)

Group 11

0.6 to 0.88 L/ha
(240 to 400 mL/acre)

Apply in 110 L/ha (45 L/ac) of water

0
  • Suppression only.
  • Repeat using a 7 to 14 day interval.
  • Do not apply more than 2.63 L/ha (1.06 L/ac) per season.
  • Do not make more than 2 sequential applications before switching to a fungicide that has a different group number.
  • Observe a plantback interval of 10 months for crops not listed on the label.
  • Toxic to earthworms and to certain beneficial insects.
  • Do not re-enter treated area for 12 hours.

Allegro 500 F

(fluazinam)

Group 29
1.16 L/ha
(470 mL/acre)

Apply in 100 L/ha (40 L/acre)
7
  • Apply as a foliar broadcast spray.
  • Repeat using a 7 to 10 day application interval.
  • Do not make more than 5 applications.
  • See label for plantback interval details.
  • Do not enter treated area for 3 days for hand weeding, and for all other activities for 24 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-Canada = Organic Materials Review Institute of Canada

 

Botrytis Neck Rot

Chemical Control of Botrytis Neck Rot

Product Rate PHI* Comments

Serenade Opti

(Bacillus subtilis)
 
Used in organics
1.7 to 2.5 kg/ha
(690 to 1000 g/acre)
0
  • Suppression only.
  • Repeat using a 7 to 10 day interval.
  • Serenade Opti (PCP# 31666) is OMRI-Canada listed.  Check with your certification body before using in an organic operation. 

Scala SC

(pyrimethanil)

Group 9
2.0 L/ha
(800 mL/acre)

Apply in at least 300 L/ha (121 L/acre) of water 
7
  • Repeat using a 7 to 14 day application interval.
  • Maximum application of 6 L/ha (2.4 L/acre) per season.
  • Do not enter treated area for 24 hours for hand thinning or 12 hours for all other activities.

Acapela

(picoxystrobin)

Group 11

0.44 to 0.88 L/ha
(180 to 400 mL/acre)

Apply in 110 L/ha (45 L/ac) of water

0
  • Repeat using a 7 to 14 day interval.
  • Do not apply more than 2.63 L/ha (1.06 L/ac) per season.
  • Do not make more than 2 sequential applications before switching to a fungicide that has a different group number.
  • Observe a plantback interval of 10 months for crops not listed on the label.
  • Toxic to earthworms and to certain beneficial insects.
  • 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).

 

Suppression of Purple Blotch

Chemical Suppression of Purple Blotch

Product Rate PHI* Comments

Inspire

(difenoconazole)

Group 3

364 to 512 mL/ha
(147 to 207 mL/acre)

Apply in 150 L/ha (60 L/acre) of water.

7
  • Provides control.
  • Repeat using a 7 to 10 day interval.
  • Do not apply more than 2.04 L/ha (825 mL/acre) per crop per season.
  • Do not make more than 2 sequential applications before alternating to a fungicide with a different mode of action.
  • May be tankmixed with Revus for labeled pests. Follow the most restrictive directions including rate, PHI, maximum applications and re-entry interval.
  • Observe a plantback interval of 60 days for crops not on label.
  • Do not re-enter treated area for 12 hours.

Switch 62.5 WG

(cyprodinil & fludioxonil)

Group 9 & 12
775 to 975 g/ha
(314 to 395 g/acre)

Apply in 200 L/ha (80 L/acre) of water
7
  • Repeat using a 7 to 14 day application interval.
  • Do not make more than 3 applications per year.
  • Observe a 30 day plantback interval for crops not listed.
  • Do not enter treated area for hand weeding for 3 days, and for all other activities do not re-enter for 12 hours.

Acapela

(picoxystrobin)

Group 11

0.44 to 0.88 L/ha
(180 to 400 mL/acre)

Apply in 110 L/ha (45 L/ac) of water

0
  • Repeat using a 7 to 14 day interval.
  • Do not apply more than 2.63 L/ha (1.06 L/ac) per season.
  • Do not make more than 2 sequential applications before switching to a fungicide that has a different group number.
  • Observe a plantback interval of 10 months for crops not listed on the label.
  • Toxic to earthworms and to certain beneficial insects.
  • Do not re-enter treated area for 12 hours.

Allegro 500 F

(fluazinam)

Group 29
1.16 L/ha
(470 mL/acre)

Apply in 100 L/ha (40 L/acre)
7
  • Apply as a foliar broadcast spray.
  • Repeat using a 7 to 10 day application interval.
  • Do not make more than 5 applications.
  • See label for plantback interval details.
  • Do not enter treated area for 3 days for hand weeding, and for all other activities for 24 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).

 

Suppression of Stemphylium Leaf Blight

Chemical Suppression of Stemphylium Leaf Blight

Product Rate PHI* Comments

Aprovia

(benzovindiflupyr)

Group 7
750 mL/ha
(300 mL/acre)

Apply in at least 150 to 600 L/ha (60 to 240 L/acre) of water
7
  • Apply when plants are 5 to 10 cm high.
  • Repeat using a 7 to 14 day interval.
  • Do not apply more than 4 times per season.
  • Do not apply more than 3 L/ha (1.2 L/acre) per season.

*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).

 

Downy Mildew

Chemical Control of Downy Mildew

Product Rate PHI* Comments

Serenade Opti

(Bacillus subtilis)
 
Used in organics
1.7 to 3.3 kg/ha
(690 to 1300 g/acre)
0
  • Suppression only.
  • Repeat using a 7 to 10 day interval.
  • Serenade Opti (PCP# 31666) is OMRI-Canada listed.  Check with your certification body before using in an organic operation.

Cueva

(copper octanoate)
 
Group M1
 
Used in organics
Use a 0.5% to 2% solution at 470 to 940 L/ha (190 to 380 L/acre) 1
  • For a 0.5% solution, mix 1 part Cueva to 200 parts water.
  • For a 2% solution, mix 1 part Cueva to 50 parts water.
  • Repeat at 7 to 10 day intervals.
  • Repeat at 5 to 7 day intervals following heavy rain or when disease pressure is high.
  • Do not make more than 15 applications per year.
  • Time applications so that 12 hours of dry weather follow application.
  • Cueva products (PCP# 31825) are OMRI-Canada listed.  Check with your certification body before using in an organic operation.
  • Do not re-enter treated area for 4 hours.

Pristine WG

(boscalid & pyraclostrobin)

Group 7 & 11
1000 to 1300 g/ ha
(400 to 520 g/acre)
7
  • Suppression only.
  • Begin applications prior to disease development and continue on a 7 to 14 day schedule.
  • Do not apply more than 6 times per season.
  • Do not make sequential applications when suppressing downy mildew, but follow up 5 to 7 days later using a fungicide from a different group.
  • Do not enter treated areas until residues have dried.

Quadris Top

(azoxystrobin/ difenoconazole)

Group 11 & 3

710 to 1000 mL/ha
(290 to 400 mL/acre)

Apply in at least 150 L/ha (60 L/acre) of water.

7
  • Repeat at 7 to 14 day intervals.
  • Do not apply more than 4 times per year.
  • Do not re-enter treated areas for 12 hours.
  • Observe a plant back interval of 60 days for crops not listed on this label or the Inspire label. 

Cabrio EG

(pyraclostrobin)

Group 11
560 to 840 g/ha
(220 to 340 g/acre)

Apply in at least 225 L/ha (90 L/acre) of water
7
  • Repeat at 10 day intervals.
  • No more than 3 applications per season.
  • Do not use treated crops for feed.
  • Do not enter treated area for 12 hours.

Reason 500SC

(fenamidone)

Group 11
400 mL/ha
(160 mL/acre)
7
  • Suppression only.
  • Repeat at 5 to 10 day intervals.
  • Do not apply more than 4 times per year. Do not apply more than 1600 mL/ha (648 mL/ac) per growing season.
  • Do not enter treated area until residues have dried.

Torrent 400SC

(cyazofamid)

Group 21

0.20 L/ha (80 mL/acre)
 
Apply in 200 to 600 L/ha (80 to 240 L/acre) of water.
0
  • Tank-mix with a non-ionic or organosilicone surfactant such as Sylgard 309 at the manufacturer's label recommendations.
  • Repeat using a 7 to 10 day interval.
  • Do not apply more than 6 times per crop per year.
  • Observe a plantback interval of 30 days for crops not listed.
  • Do not enter treated area for 12 hours.

Revus

(mandipropamid)

Group 40

400 mL/ha
(160 mL/acre )

Apply in 100 L/ha (40L/acre) of water

7
  • Use a non-ionic adjuvant (0.25% v/v) or mineral oil at 1.0%.
  • Repeat at 7 day intervals.
  • Do not apply more than 4 times per year.
  • Do not apply more than 1.6 L/ha (647 mL/ac) per season.  
  • Do not make more than 2 consecutive applications of Revus before alternating with a non-Group 40 fungicide.
  • The number of Group 40 fungicide applications must not be greater than 50% of the total number of intended applications for disease control. 
  • Do not enter treated area for 12 hours.

Acrobat 50 WP

(dimethomorph)
 
Group 40
 
Note:  no longer produced.

450 g/ha
(182 g/acre)

Apply in 200 L/ha (80 L/acre) of water.

0
  • Suppression only.
  • Apply as a tank mix with another fungicide in this table that is active against downy mildew. Observe most restrictive directions including rate, PHI and re-entry interval.
  • Repeat using a 5 to 7 day spray interval.
  • Maximum of 5 applications per season
  • Do not re-enter treated area for 12 hours.

Forum

(dimethomorph)

Group 40

450 mL/ha

(182 mL/acre)

Apply in 200 L/ha (80 L/acre) of water.

0
  • Suppression only.
  • Apply as a tank mix with another fungicide registered for downy mildew. Observe most restrictive directions including rate, PHI and re-entry interval.
  • Repeat using a 5 to 7 day spray interval.
  • Maximum of 5 applications per season.
  • Do not make more than 2 sequential applications before alternating to another non-group 40 fungicide for at least 1 application.
  • Do not handle more than 81 L per day.
  • Do not re-enter treated area for 12 hours.

Phostrol

(mono- and dibasic sodium, potassium, and ammonium phosphites)
 
Group 33
2.9 to 4.3 L/ha (1.2 to 1.7 L/acre)
 
Apply in 225 L/ha (90 L/acre) of water
0
  • Suppression only.
  • Repeat using a 7 to 14 day application interval.
  • Do not make more than 7 applications per season.
  • Do no re-enter treated area for 12 hours.

Zampro

(ametoctradin & dimethomorph)

Group 40 & 45

1.0 L/ha
(400 mL  /acre)

Apply in 200 L/ha (80 L/acre) of water.
0
  • Repeat at 5 to 7 day intervals.
  • Do not apply more than 3 times per season.
  • Use a spreading/penetrating adjuvant.
  • Do not re-enter treated area for 12 hours.
  • Observe a plantback interval of 30 days for all crops not on the label.

Orondis

(oxathiapiprolin)

Group 49

88 to 350 mL/ha (35 to 140 mL/acre

Apply in 110 L/ha (45 L/acre) of water.

0
  • Repeat using a 5 to 10 day interval.
  • Where multiple crop cycles are produced in the same year, do not make more than 6 applications/ha/year.
  • Do not apply more than 1.40 L/ha (570 mL/acre) per season.
  • 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-Canada = Organic Materials Review Institute of Canada

 

Control of Garlic Rust

Chemical Control of Garlic Rust

Product Rate PHI* Comments

Aprovia

(benzovindiflupyr)

Group 7
750 mL/ha
(300 mL/acre)

Apply in 150 to 600 L/ha (60 to 240 L/acre) of water
7
  • Apply when plants are 5 to 10 cm high.
  • Repeat using a 7 to 14 day interval.
  • Do not apply more than 4 times per season.
  • Do not apply more than 3 L/ha (1.2 L/acre) per season.

*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).