Snap Beans

Last updated on December 19, 2023

Beans (snap variety)

Growing Snap Beans

 

Varieties

Fresh Market

Green

Jade, Bronco, Ambra, Savannah, Caprice, Sahara, Valentino.

Yellow Wax

Goldrush, Unidor, Rocdor, HM5101

Process Market

Consult processors, HM5101

See your seed dealer for the most recent variety recommendations.

 

Seed Treatment

Purchase fungicide treated seed if possible, otherwise treat seed with Thiram, Captan or Kocide. seed protectants, according to manufacturers’ directions.

For control of Pythium damping off, use seed treated with Apron XL LS seed protectant.  For control of damping off caused by Pythium spp., Fusarium spp. and Rhizoctonia spp.; and for seedling blight caused by Pythium spp., use seed treated with Apron MAXX RTA.

For control of seed corn maggot and wireworm, use seed treated with Cruiser 5FS

 

Soil Temperature

Good germination is obtained at soil temperatures of 16 to 29°C. Seed rot is a serious problem at lower temperatures.

 

Seeding and Spacing

Always handle bean seed with care, as rough handling lowers the percentage of germination.

For bush beans, seed 10 to 16 seeds/50 cm of row 50 to 90 cm apart or as required for a particular mechanical harvester. Losses due to gray and white mold are greatest at close spacing. Aim for a final plant stand of 300,000 plants per hectare (12,000/acre). This is usually 75 to 100 kg/ha (30 to 40 kg/acre) of seed depending upon seed size and germination percentage.

For pole beans, seed 7 to 10 seeds/50 cm of row and space rows 1.65 m apart.

Sow at a uniform depth of 4 cm if pre-emergence herbicides are to be used.

 

Fertilizer

A soil test is necessary to determine phosphate and potash requirements. Use the Vegetable Production Guide: Nutrient Management (PDF) for recommendations based on soil test results.

Lime should be applied if the pH is below 5.6 on mineral soils.

Bush Beans

Broadcast and disc in required potash prior to seeding. At time of seeding, band 15 to 40 kg/ha (6 to 16 kg/acre) of nitrogen and all the required phosphate 5 cm to the side of the seed, and 7.5 to 10 cm deep.

Pole Beans

Broadcast and disc in the required potash. At time of seeding band 70 kg/ha (28 kg/ acre) of nitrogen and all the phosphate 5 cm to the side of the seed and 7.5 to 10 cm deep. Just prior to blossoming, side-dress with 40 kg/ha (16 kg/acre) of nitrogen.

Magnesium may be required on light soils.

 

Bean Leaf Stages

Bean leaf emerging from soil

Bean leaf sprouting

Bean stalk with trifoliate leaves

 

 

Snap Bean Weed Management

 

Pre-plant Incorporation

Pre-plant Incorporation: Herbicide Application Rates

Product Rate PHI* Comments

Eptam 8-E

(EPTC)

Group 15
4.25 to 5.5
L/ha (1.7 to 2.2 L/acre)
N/A
  • Controls barnyard grass and many broadleaved weeds, but shepherd’s-purse and lady’s-thumb are resistant.
  • Suppresses quackgrass on light, sandy soils.
  • Incorporate immediately to 8 to 10 cm depth as it is readily lost on warm, moist soils.
  • Use the low rate on light, sandy soils and the high rate on heavy soils.
  • Do not use on soils with greater than 12% organic matter.
  • If weather is dry at time of treatment, delay seeding of beans for 7 to 10 days.
  • For controlling resistant weeds other herbicides listed below are necessary
  • See label for incorporation instructions.
  • Do not enter treated area for 24 hours.
  • Can also be tank-mixed with Sandea PPI or at planting.  See Sandea label for rates, precautions and instructions.

Bonanza 480

(trifluralin)

Group 3
1.25 to 2.3 L/ha
(500 to 900 mL/acre)

Apply in a minimum of 100 L/ha (40 L/acre) of water at 275 kPa.
N/A
  • Controls seedling grasses and some broadleaved weeds.
  • Lady’s-thumb, nightshades, groundsel, shepherd’s-purse, cudweed and mustards are not controlled.
  • Rates vary with soil types, see label for details.
  • Apply treatment from 3 weeks before planting up to the time of planting and incorporate thoroughly within 24 hours to 8 to 10 cm deep with a double disc set at 10 cm.
  • Use the lower rate on sandy soil, the higher rate on heavier soils.
  • Effectiveness is reduced on cold, wet soils or on mineral soils with less than 2% or greater than 15% organic matter.
  • If manure is spread prior to application ensure it has been thoroughly mixed into soil with at least 2 tillage operations prior to application.

Dual II Magnum

(S-metolachlor)

Group 15
1.15 to 1.75 L/ha
(0.46 to 0.7 L/acre)
N/A
  • Use the higher rate for heavier weed problems.
  • For redroot pigweed suppression apply a minimum of 1.25 L/ha (0.5 L/acre).
  • Beans should be seeded at least 4 cm deep or crop injury my occur.
  • Do not enter treated areas for 12 hours.
  • 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.

Prowl H2O

(pendimethalin)

Group 3

2.37 L/ha
(1 L/acre)

Apply in at least 200 L/ha (80 L/acre) of water
50
  • Controls green foxtail and redroot pigweed as they germinate, but will not control established weeds.
  • Suppression only for lamb's-quarters.
  • Apply once per season.
  • Do not apply more than 1 year in sequence.
  • Adequate soil moisture improves control.
  • In the event of crop failure, treated land can be reseeded to corn.  See label for planting directions.
  • Rotational crops such as field corn and dry bulb onions may be planted the year follwing treatment.
  • Fall seeded crops such as winter wheat, winter barley and winter rapeseed should not be planted on land treated the previous spring.
  • Do not re-enter treated area 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).

 

Pre-emergence

Pre-emergence: Herbicide Application Rates

Product Rate PHI* Comments

Sandea

(halosulfuron)

Group 2
35 to 70 g/ha (14.2 to 28.3 g/acre)
 
Apply in 140 L/ha (55 L/acre) of water
30
  • Apply after planting, but prior to soil cracking.
  • If weeds are present prior to crop emergence, use with a non-ionic adjuvant or crop oil concentrate.
  • Use lower rate on lighter textured soils with low organic matter.
  • Do not apply more than 70 g/ha (28.3 g/acre) per season.
  • Can be applied as a broadcast or band application.
  • For band applications, use proportionally less spray mixture based on the area actually sprayed so that a full rate is not concentrated into the band.
  • Controls labelled broadleaf weeds including ladysthumb, wild mustard and redroot pigweed.
  • Suppresses nutsedge.
  • 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.
  • Incorporate with 0.5 to 1.25 cm irrigation to improve weed control.  
  • May cause temporary stunting.  
  • Observe plantback interval of 15 months for cabbage and carrots, 18 months for broccoli and cauliflower, 24 months for spinach and 36 months for beets.  See label for other crops listed.
  • 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

Centurion/Select

(clethodim)
0.19 L/ha
(77 mL/acre

Apply in 110 L/ha (45 L/acre) of water at 275 kPa
21
  • Apply post-emergence of weeds and crop.
  • Do not apply more than 1 time per season.
  • Do not apply more than 0.38 L/ha (154 mL/acre) per season.
  • Centurion/Select is to be used only 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.

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:

650 mL/ha (263 mL/acre)

15
  • Do not apply more than 650 mL/ha (263 mL/acre).
  • 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 when quackgrass is in the 1 to 3 leaf stage.
  • Observe a 30 day plant back interval on crops not listed.
  • Do not enter treated area for 12 hours.

Assure II

(quizalofop-P-ethyl)

Group 1
380 mL to 750 mL/ha
(150 to 300 mL/acre)

Apply with Merge at 5 to 10 L per 1000 L of spray solution, or Sure-Mix at 0.5% (0.5 L per 100 L of spray solution)
30
  • Controls annual grasses and quackgrass.
  • See label for rates, weed types, and weed leaf stages.
  • Apply at the 2 to 5 leaf stage of annual grasses and up to the 3 leaf stage for quackgrass.
  • Do not make more than 1 application per year.
  • Rainfall within 1 hour of application may reduce effectiveness.
  • Do not apply within 7 days of using other herbicides or wait at least 24 hours before using other herbicides after making an application of Assure or Yuma.
  • Use flat fan nozzles. Do not use flood jet nozzles.

Yuma


(quizalofop-P-ethyl)

Group 1
380 mL to 750 mL/ha
(150 to 300 mL/acre)

Apply with Merge at 5 to 10 L per 1000 L of spray solution, or Sure-Mix at 0.5% (0.5 L per 100 L of spray solution)
30
  • Controls annual grasses and quackgrass.
  • See label for rates, weed types, and weed leaf stages.
  • Apply at the 2 to 5 leaf stage of annual grasses and up to the 3 leaf stage for quackgrass.
  • Do not make more than 1 application per year.
  • Rainfall within 1 hour of application may reduce effectiveness.
  • Do not apply within 7 days of using other herbicides or wait at least 24 hours before using other herbicides after making an application of Assure or Yuma.
  • Use flat fan nozzles. Do not use flood jet nozzles.

Basagran

(bentazon)

Group 6

Plus
 

Assist

1.75 to 2.25 L/ha (705 to 910 mL/acre)



 

Plus

1.0 to 2.0 L/ha (0.4 to 0.8 mL/acre)

Apply in 100 to 400 L/ha (40 to 160 L/acre) of water at 275 to 425 kPa

N/A
  • Apply after the first bean trifoliate leaf is fully expanded (see leaf stage diagram, in beans section)
  • The lower rate of 1.75 L/ha (0.7 L/acre) may be used if only easier to control weeds such as lady’s thumb, wild mustard and shepherd’s-purse are present.
  • Under hot and humid conditions use 1.0 L/ha of Assist.
  • Stress (i.e. drought, injury, cool weather) may result in crop injury and reduced weed control.
  • Rainfall within 6 to 8 hours of application may reduce effectiveness.
  • Basagran will not control grasses.
  • Do not add a nitrogen source when tank mixing.
  • Do not graze treated crops.
  • Do not enter treated area for 12 hours.

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, leaves or blooms of the crop.
  • Apply only once per growing season.
  • Do not apply if used as a pre-plant burn-down in the same season.
  • Review the Vegetable Production Guide: Pest Management (PDF) or pre-plant burn-down precautions.

Sandea

(halosulfuron)

 

Group 1

Post-emergence:

35 to 47 g/ha

(14.2 to 19.0 g/acre)

 

Row Middle/Furrow Applications:

35 to 70 g/ha

(14.2 to 28.3 g/acre)

40

Post-emergence directions:

  • Apply after the crop has reached the 2 to 4 trifoliate leaf stage, but before flowering.
  • Use lower rate on lighter textured soils with low organic matter.
  • Directed sprays are recommended to prevent crop injury.

Row middle/furrow applications directions:

  • Apply between the rows of the crop.
  • Avoid contact of the herbicide with the planted crop.
  • Reduce rate and spray volume in proportion to area actually sprayed.

General use directions:

  • Apply in 140 L/ha (55 L/acre) of water.
  • A sequential application may be necessary for some annual and perennial weeds.
  • Repeat using a 21 day interval.
  • Do not apply more than 70 g/ha (28.3 g/acre) of product 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.
  • Controls broadleaf weeds including ladysthumb, wild mustard, yellow nutsedge and redroot pigweed.
  • Suppresses horsetail, 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.Heavy infestations may require sequential applications.
  • May cause temporary stunting.
  • Observe plantback interval of 15 months for cabbage and carrots, 18 months for broccoli and cauliflower, 24 months for spinach and 36 months for beets.  See label for other crops listed.
  • 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).

 

Snap Bean Insect Management

 

Aphids

Aphids are small (1mm) pear-shaped, soft, black or green sucking insects clustered on growing tips or on undersides of leaves. They may be winged or wingless. They can cause wilting and yellowing of plants.

Spray (in sufficient water to provide thorough coverage on tops and bottoms of leaves) with one of the products in the table below.

Chemical Control of Aphids

Product Rate PHI* Comments

Diazinon 50 W

(diazinon)
 
Group 1B
1.0 kg/ha
(0.4 kg/acre)
7
  • Best control is obtained when temperature is above 20°C.
  • Highly toxic to bees.

Malathion 85E

(malathion)

Group 1B
735 to 1345 mL/ha
(300 to 545 mL/acre)
 
Apply in 1000 L/ha (405 L/acre) of water 
3
  • Repeat using a 7 day interval.
  • Do not make more than 2 applications per year.
  • Best control is obtained when 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 24 hours.

Cygon 480/ Lagon 480 E

(dimethoate)
 
Group 1B

700 to 1000 mL/ha
(280 to 405 mL/acre)

7
  • Apply as a groundspray using a closed cab.
  • Repeat using a 7 day interval.
  • No more than 2 applications per season.
  • Use sufficient water for good coverage
  • Do not feed or allow livestock to graze treated foliage.
  • Toxic to bees.  Avoid applying when the crop is in bloom.  If applications must be made during bloom, apply in the evening when most bees are not foraging.
  • Do not re-enter treated area for 12 hours.

Matador 120 EC/ Silencer 120 EC

(lambda- cyhalothrin)

Group 3

83 to 233 mL/ha
(34 to 94 mL/acre)

Apply in 100 to 200 L/ha (40 to 80 L/acre) of water
7
  • Repeat using a 7 day interval.
  • Do not make more than 3 applications per season.
  • Do not graze or harvest treated crop for livestock feed.
  • Do not apply more than 3 times per season.
  • Toxic to bees. Avoid spraying when bees are foraging.
  • If the field slopes downward to water, construct and maintain a vegetative filter strip.  Check label for details.
  • Check label for personal protective equipment requirements.
  • Do not enter treated area for 12 hours.

Assail 70WP

(acetamiprid)
 
Group 4
56 to 86 g/ha
(23 to 35 g/acre)
7
  • Apply at a 7 day spray interval.
  • Maximum of 3 applications per season.
  • Toxic to bees.  Do not apply to flowering crops or weeds if bees are visiting the treatment area.
  • Do not enter treated area for 12 hours.

Admire 240F

(imidacloprid)
 
Group 4
Soil application:
7.5 mL per 100m of row
 
(see rate conversion chart of label for row spacing calculations)
21
  • Use one of the following methods:
  • Apply specified dosage in 2000 L/ha (800 L/ac) of water as a narrow (5 cm or less) surface band over the seedline during planting.
  • Seedlings:  apply in 200 L/ha (80 L/ac) of water as a subsurface side-dress on both sides of each row. Product must be incorporated into the root zone.
  • Post-seeding drench:  use higher water volumes to thoroughly wet the soil
  • Do not apply more than once per season as a soil application.
  • Do not make any subsequent application of a group 4 insecticide.

Admire 240F

(imidacloprid)
 
Group 4
Foliar application:
200 mL/ha
(80 mL/acre)
7
  • Repeat using a 7 day interval.
  • Do not make more than 2 applications per year.
  • Do not follow a soil application with a foliar application of Admire 240F.
  • Do not re-enter treated area for 24 hours.

Sivanto Prime

(flupyradifurone)
 
Group 4D

500 to 750 mL/ha
(200 to 300 mL/acre)

Apply in at least 100 L/ha (40 L/acre) of water
7
  • Repeat at a 10 day interval.
  • Do not exceed a total of 2000 mL/ha (810 mL/acre) of product per season.
  • Toxic to bees.  Do not apply to flowering crops or weeds if bees are visiting the treatment area.
  • Do not enter treated areas for 12 hours.

Beleaf 50SG

(flonicamid)

Group 29
120 to 160 g/ha
(50 to 65 g/acre)

Apply in 94 L/ha (38 L/acre) of water
7
  • Repeat at 7 day intervals.
  • Do not apply more than 3 times per year.
  • Observe a 30 day plantback interval for crops not listed.
  • Do not re-enter treated area for 12 hours.

Movento 240SC

(spirotetramat)

Group 23
185 to 275 mL/ha
(75 to 110 mL/acre)

Apply in 300L/ha (120 L/acre) of water
1
  • Use with one of the following adjuvants: non-ionic (eg. Agral 90 or Ag-Surf) or methylated seed oil (eg. Hasten).
  • Do not apply more than 730 mL/ha (295 mL/acre) per crop per season.
  • Toxic to bees. Avoid spraying when crop is in bloom.
  • Do not enter treated area for 12 hours.

Pyganic

(pyrethrins)

Used in organics
2.32 to 4.65 L/ha
(0.9 to 1.9 L/acre)
0
  • Final mix should be buffered to pH of 5.5 to 7.0
  • Apply at a 7 day spray interval.
  • Maximum of 8 applications per season.
  • Do not wet to the point of run off.
  • Highly toxic to bees. Avoid use when bees are actively foraging. Best applied in early morning or evening.
  • Do not enter treated area for 12 hours.
  • Pyganic products are OMRI-USA listed.  Check with your certification body before using in an organic operation.

*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

 

Seedcorn Maggots

These are small, cream-coloured, legless maggots which attack germinating seeds under cold, wet soil conditions. Adults are flies, slightly smaller than houseflies.

Control

Plant insecticide/fungicide treated seed.

 

Slugs

These slow-moving, soft-bodied, slimy, legless creatures are found in various sizes up to 10 cm. They eat holes in leaves and leave a trail of mucus which makes the plants unsightly.

Control

Where slugs may be a problem, treatment should be applied before planting or while plants are in the seedling stage. Baits are most effective for slug control early in the season; control is difficult later when slugs are feeding on maturing plants. Apply Sluggo (iron phospate) or Deadline M-PS (metaldehyde) at the label rate. Treatments should be made in the evening to the soil between the rows and the headlands. Avoid direct application to plants. Do not apply metaldehyde to bean plants after flowering.

 

Wireworms

Wireworms are yellowish-brown, shiny, slender, hard-bodied worms, which bore into seeds and seedlings. Larvae start to move to the root zone in the spring when soil temperatures reach 10°C. Infestations are often heaviest in newly broken grassland.

Control

Consult the “Wireworms” section of the Vegetable Production Guide: Pest Management (PDF, 1.2 MB).

 

Snap Bean Disease Management

 

Bacterial Blights (Common and Halo)

Symptoms are water-soaked spots with yellow borders on leaves, reddish cankers on stems and water-soaked spots with reddish margins on pods.

Control

Use disease-free seed. Cultivate, weed and harvest only when dry. Rogue out and destroy affected plants. Rotate crops for at least two years. If a spray program is required, see products listed in the table below.

Chemical Control of Bacterial Blight

Product Rate PHI* Comments

Oxidate 2.0

(hydrogen peroxide & peroxyacetic acid)

Used in organics

Dilute 1.0 L product in 100 L water (1.0% v:v) 0
  • Partial suppression only.
  • Use a non-ionic surfactant at 0.10% to 0.125% v/v (0.1 L to 0.125 L per 100 L of spray solution).
  • Repeat using a 7 day application interval.
  • Good coverage is required.
  • Do not apply more than 8 times per season.
  • Do not apply more than 93.5 L/ha (37.8 L/acre) per application.
  • Toxic to bees.  Do not apply if bees are visiting the treatment area.
  • Toxic to certain beneficial insects.
  • Oxidate 2.0 (PCP# 32907) is OMRI-Canada listed.  Check with your certification body before using in an organic operation.
  • Do not re-enter treated area for 4 hours or until sprays have dried. 

Parasol F

(copper hydroxide)
 
Group M1
2.3 to 3.12 L/ha
(0.9 to 1.25 L/acre)
1
  • Apply at 7 to 14 day intervals.

Kocide 2000

(copper hydroxide)
 
Group M
 
Used in organics
1.6-2.3 kg/ha
(600 to 900 g /acre)
1
  • Make 1st application when plants are 15 cm tall.
  • Repeat using a 7 to 14 day interval.
  • Maximum 10 applications per year.
  • Kocide 2000 (PCP# 27348) 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.

*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

 

Grey Mould (Botrytis)

Symptoms consist of grey mould over the surface of the leaves and pods or on the stems of young seedlings.

Control

Severe losses frequently occur if wet weather occurs during and just after bloom. These losses may be reduced by increasing plant spacing; decreasing plant vigor and canopy development by restricting fertilizer and water availability; and by orienting rows with the prevailing winds. Spray with one of the products in the table below.

Overwintering sclerotia on plant debris and weeds should be disced deep. Rotate with cereals or corn as they rarely harbour Botrytis.

Chemical Control of Grey Mould

Product Rate PHI* Comments

Lance WDG

(boscalid)

Group 7
420 g/ha
(160 g/acre)

Apply in at least 100 L/ha (40 L/acre) of water
7
  • Apply at 20 to 50% bloom.
  • Maximum of 2 applications per season.
  • Apply at 7 to 14 day intervals.
  • Do not enter treated area for 12 hours.
  • For crops not on the label, observe a plant back interval of 14 days.

Fontelis

(penthiopyrad)

Group 7
1.0 to 2.25 L/ha
(400 to 910 mL/acre)

Apply in 110 L/ha (45 L/acre) of water
0
  • Also controls Alternaria blight leafspot.  Check label.
  • Repeat at 7 to 14 day intervals.
  • Do not apply more than 5.25 L/ha (2.2 L/acre) per season.
  • Do not make more than 2 sequential applications before switching to a fungicide with a different mode of action.
  • Do not re-enter for 12 hours.

Acapela

(picoxystrobin)

Group 11

0.88 L/ha
400 mL/acre)

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

0
  • Suppression only.
  • Do not make more than 1 application before switching to a fungicide that has a different group number.
  • Repeat using a 7 to 10 day interval.
  • Do not apply more than 1.75 L/ha (708 mL/ac) per season.
  • 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.

Switch 62.5 WG

(cyprodinil & fludioxonil)

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

Apply in at least 175 to 225 L/ha (71 to 91 L/acre) of water
7
  • Repeat applications at 7 day intervals.
  • Do not make more than 2 sequential applications of Switch or other fungicides in the same group (9 or 12) in a season.
  • Do not apply more than 1.1 kg/ha (400 g/acre) of cyprodinil products and 730 g/ha (300 g/acre) of fludioxonil products per crop.
  • Observe a 30 day plantback interval for crops not listed.
  • 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-Canada = Organic Materials Review Institute of Canada

 

White Mould (Sclerotinia)

This white, cottony mould is worse in wet seasons. It causes damping-off of seedlings and a watery soft rot of plants, bean pods, and stems in which small hard black sclerotia are produced. This mould spreads rapidly through beans after harvest.

Control

Rotate with resistant or immune crops such as beets, onions, spinach, corn, cereals or grasses for two years before planting other susceptible crops such as carrots, lettuce, parsnips, cucurbits, cole crops or celery. Seed after May 15. Do not apply excess overhead irrigation. Irrigate early in the morning so plants will dry by evening. Reduce the density of the plant canopy to enhance fast drying of foliage and soil. Cultivate and pick when dry. Sclerotia can survive in the soil for several years (5 or more). If feasible, flood land in winter for a minimum of 30 days to kill the overwintering fungus.

In fields with a history of white mould, the sprays in any of the Beans (Snap) Disease Management tables are useful. Contans WG (Coniothyrium minitans) is a soil treatment registered for suppression. It must be applied to the soil and incorporated as thoroughly and uniformly as possible at least 3 months prior to an anticipated Sclerotinia outbreak.

Chemical Control of White Mould

Product Rate PHI* Comments

Lance WDG

(boscalid)

Group 7
560 to 770 g/ha
(224 to 308 g/acre)

Apply in at least 100 L/ha (40 L/acre) of water.
7
  • Apply at 20 to 50% bloom.
  • Maximum of 2 applications per season.
  • Apply at 7 to 14 day intervals if conditions for disease development continue.
  • Do not enter treated area for 12 hours.
  • For crops not on the label, observe a plant-back interval of 14 days.

Switch 62.5 WG

(cyprodinil & fludioxonil)

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

Apply in at least 175 to 225 L/ha (71 to 91 L/acre) of water
7
  • Make the first application at 20% bloom.
  • Repeat applications at 7 day intervals.
  • Do not make more than 2 sequential applications of Switch or other fungicides in the same group (9 or 12) in a season.
  • Do not apply more than 1.1 kg/ha (400 g/acre) of cyprodinil products and 730 g/ha (300 g/acre) of fludioxonil products per crop.
  • Observe a 30 day plantback interval for crops not listed.
  • Do not enter treated area for 12 hours.

Acapela

(picoxystrobin)

Group 11

0.88 L/ha
400 mL/acre)

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

0
  • Suppression only.
  • Do not make more than 1 application before switching to a fungicide that has a different group number.
  • Repeat using a 7 to 10 day interval.
  • Do not apply more than 1.75 L/ha (708 mL/ac) per season.
  • 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 500F

(fluazinam)

Group 29
0.6 to 1.0 L/ha
(200 to 400 mL/acre)

Apply in 300 to 1000 L/ha (120 to 400 L/acre) of water
14
  • Begin application when 10% of plants have at least one open bloom.
  • Make 2nd application 7 to 10 days later, but not later than when 50% of the plants have at least one open bloom.
  • Maximum of 2 applications per year.
  • Areas treated can be planted to potatoes as soon as practical. For other root crops and leafy vegetables the plant back interval (PBI) is 30 days. For all other crops, the PBI is 70 days.
  • Do not enter treated area 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

 

Root Rot (Suppression)

May be due to Fusarium, Rhizoctonia, Pythium or other soil organisms. Affected plants are slow to emerge and remain stunted with yellowish leaves which may drop off early. At the ground level and below, the main root shows a red to black discoloration. Feeder roots may be sparse or nearly lacking.

Control

  • Badly affected fields should be rotated into corn, cereals or grasses, but avoid seeding into a field containing undecomposed green manure.
  • Use only fresh, vigorous seed which has been treated with Apron and/or a combination of insecticide-fungicide. See the “Seed Treatment” section of the Vegetable Production Guide: Planting (PDF) for more information.
  • Sub-soil heavy clay soils prior to seeding.
  • Fields with a history of root rot should be planted last when the soil is as warm as possible.

Chemical Control of Root Rot (Suppression)

Product Rate PHI* Comments

Serenade Soil

(QST 713 strain of dried Bacillus subtilis)
 
Used in organics

 

2.7 to 14 L/ha (1.1 to 5.7 L/acre) 0
  • Serenade Soil (PCP# 30647) is OMRI-Canada listed.  Check with your certification body before using in an organic operation.

Surface applications:

  • Apply as a 15 cm band over the top of the seed row as a broadcast spray after planting.
  • Ensure incorporation into the seed zone within 24 hours of application via rainfall or overhead irrigation.

Post-plant applications:

  • After crop germination, additional applications may be made to the soil as a drench or spray directed towards the base of the plant.
  • Irrigate to move material into the seed or root zone.
  • Repeat at 21 to 28 day intervals.

*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