We also hypothesized that scouting and spraying the sprouts would provide some control. These insecticides were applied when thresholds were met through the scouting protocol put forth by the University of California's Statewide Integrated Pest Management Program, found at http://ipm.ucanr.edu/PMG/r108300811.html. The treatments were laid out as follows: The first treatment was the control, where no form of aphid control was applied. If you’re already dealing with aphids and you want to control them naturally, try: Finally, if you want to prevent aphids from occurring, be sure to take the following steps: Justine Harrington is based in Austin, where she writes about current trends in health, wellness, community, gardening and sustainability. Also, ants tend to be attracted to the honeydew left by aphids, so an ant infestation may be symptomatic of an aphid problem. Feeding injury from cabbage aphid includes wrinkled, downw… You’ll still probably have to peel and discard the outer leaves. phone: (603) 862-1520  Hours: M-F, 8 a.m.- 5 p.m. Think of it as a zen exercise; makes it very contemplative, calming. Extended production is pos-sible as plants will tolerate temperatures down to 20 ... Brussels sprouts can be sold in pint or quart baskets or bags. Brussel sprouts can power batteries. The aphids multiplied very quickly from early September until mid-October. The alyssum attracted the most syrphid flies. Aphid-infested brassicas will typically grow slowly or incompletely. Brussels sprouts (‘Brassica oleracea’) are healthy, delicious, long-season vegetables that belong to the cabbage family. Hence, organic sprouts are hard to find. University of Connecticut recommends a threshold of 10% infested plants in cabbage, broccoli, cauliflower and Brussels sprouts after heads or sprouts begin to form. Their edible heads—like the sprouts on a brussels sprout plant—may appear damaged, stunted, or sickly. Brussels sprouts are not difficult to grow but they are heavy feeders and need supplemental fertilization or heavily amended soil. The field was fertilized prior to planting based on soil test recommendations, with 120 lbs/acre of N and 150 lbs/acre of K2O using a combination of 27-0- 0 and 0-0-22. We scouted for caterpillars and controlled them with Bt (Dipel DF, Valent USA) when necessary. During these trials, we experienced severe infestations of cabbage aphids. The cilantro and phacelia also attracted a decent number, but stopped flowering then died early in the season. We collected data every other week beginning on Aug 3rd, until Nov 4th on the number of aphids and all other insects observed on the Brussels sprouts as well as on the flowers. Cabbage aphids are green gray with a white, waxy coating. Fall harvest in Kentucky is the most practical and rewarding. Brussels sprouts always get aphids worst, but I think that if you continue to keep them in check by consistently blasting them with water then you will get a harvest. Sow seed directly into the garden in mid-summer and provide plenty of water for best growth. The sprouts form at the base of each leaf in a long stem. Rotating organic insecticides Azera and M-pede controlled cabbage aphids on Brussels sprouts very well. First, check the undersides of the leaves; you may see the bugs themselves, or you may notice the sticky residue they leave behind after feeding. Growers across the globe and in Northeastern United States have reported economically damaging populations of cabbage aphid (Brevicoryne brassicae) in Brussels sprouts (Brassicacea). These plants are easy to care for, although pest control and prevention are crucial if you want your Brussels sprouts to remain healthy. Aphids are usually present in spring and summer, although populations can increase by late summer and last well into fall. Would different planting times for the flowers provide better control? https://www.kellogggarden.com/blog/gardening/growing-brussel-sprouts The phacelia and cilantro were seeded on 6/2/2016, and all flowers were transplanted on 6/27/2016. Photo credit: Alan Eaton, IPM Extension Specialist and professor at UNH. Aphids are small, gray-green, soft-bodied insects that are typically found in clusters on new-growth cabbage plants, like Brussels sprouts. Applying insecticidal soap to Brussels sprouts on a hot, sunny day can potentially injure the plants. Insecticidal soap sprays, however, may be phytotoxic under some conditions and rates, especially in Brussels sprouts and cabbage. They prefer to feed on the youngest leaves and flowering parts and are often found deep within the heads of cabbages or Brussels sprouts. Many varieties can t… Populations can fluctuate year to year—infestation rates can be damagingly high one year and almost zero in the subsequent year—possibly due to environmental factors, including rain, which can wash off the loosely attached aphids, and entomopathogenic fungi that attack the aphids and are more prevalent in wet conditions. Late-maturing Brussels sprouts and cabbage are at high risk for damage by cabbage aphids. All aphids are soft-bodied and pear-shaped with a pair of cornicles, or little horns, projecting from the rear end of their abdomens. In 2016, we evaluated three different strategies to manage cabbage aphid in Brussels sprouts: 1) nothing, 2) organic insecticides, and 3) interplanting with a mix of flowers. This graph shows that the plots controlled by organic insecticide had greater than 80% clean sprouts at harvest time. Cabbage aphids seemed to really start multiplying at the beginning of September. Below is a table of our history of pesticide applications to control cabbage aphid: Amount Sprayed (Dilution): 2.5 oz (2 oz/gal), Amount Sprayed (Dilution): 7.5 oz (2.5 oz/gal), Amount Sprayed (Dilution): 8 oz (2 oz/gal), Amount Sprayed (Dilution): 10 oz (2.5 oz/gal), Amount Sprayed (Dilution): 10 oz (2 oz/gal). Cabbage aphids are pests only of brassicas, with cabbage, cauliflower, broccoli, and Brussels sprouts being most severely affected. Organic Spray Treatment: We scouted for aphids weekly and sprayed when the aphid levels met the economic thresholds described by University of California’s IPM resources. Create a timeline of cabbage aphid levels throughout the growing season. Though not specifically tested, we were also able to document the effectiveness of scouting with economic thresholds to determine when to apply pesticides. We irrigated via drip irrigation for approximately two hours based on feel of the soil, which typically resulted in irrigation 2X per week. However, the difference was not statistically significant. Some of the more common species are listed below. It also shows that with light cleaning, about 90% of the sprouts in the organic insecticide plots were marketable. However, soils that have been worked prior to planting are too loose to support good growth. Most mature aphids are … However, if a large aphid population has been feeding on your Brussels sprouts, it can cause the wilting and yellowing of leaves, and possibly even other damage (although it rarely kills the plant). A single harvest of the entire plant means that Always follow manufacturer instructions when working with an oil or soap and apply the material on a mild, cloudy day to plants that are not under water stress, if possible. Preventing Problems: Pull up and compost old plants, because cabbage aphids can overwinter in dead plant tissue. Generally speaking (and especially if aphids are not evident), you don’t have to wash Brussels sprouts because you are already “cleaning” them by trimming off the bottom and then peeling away a few outer leaves. If the cilantro and phacelia had been planted multiple times in sequence plantings, they may have kept flowering and attracted more insect enemies. The control plot yielded 58% of the sprouts marketable with light cleaning, and the flower plot yielded about 43% of the sprouts marketable with light cleaning. We sampled 6 leaves (2 lower, 2 middle, 2 upper) on 6 plants per plot. Beds were laid with 6 feet between bed centers. In 2016, we evaluated three different strategies to manage cabbage aphid in Brussels sprouts: 1) nothing, 2) organic insecticides, and 3) interplanting with a mix of flowers. Scouting only took us about 30 minutes every week. Our research raises several questions for future research: Many of our brussels sprouts were donated to the Cornucopia Food Pantry in Durham, NH. Sprouts are harvested in fall when cool weather produces best flavor. These flowers were planted in random formation in the middle row of each of the four flower treatments. From conversations with growers in the region, we came to realize that many growers, especially organic growers, were struggling with cabbage aphid management We decided to conduct a study to compare two different methods of managing cabbage aphids: intercropping with beneficial flowers and using a rotation between two organic insecticides. Rather than using a harmful insecticide to kill off aphids, there are several natural ways you can both manage an aphid infestation and prevent it from happening in the first place. Clip off and compost stems holding aphid clusters. … In 2013, a battery made of 1000 sprouts generated 63 volts, which were used to light up an eight-foot Christmas tree in Southbank, London. The second treatment was a rotation of two organic insecticides, insecticidal soap M-pede (Gowan Company, Yuma AZ) and Azera (Valent, Walnut Creek CA). However, the flowers did attract more insect enemies of aphids, notably parasitic wasps and syrphid flies. Brussels sprouts are a cultivar of the cabbage family, which are grown for their small, edible leafy green buds (which resemble tiny cabbages). The crops attacked include cabbage, brussels sprouts, kale, cauliflower, as well as wild mustard and shepherd's purse. We also hypothesized that scouting and spraying the sprouts would provide some control. We hypothesized that mixing flowers in with the Brussels sprouts would provide some control of cabbage aphid levels on the sprouts by attracting insect enemies of the aphid. The pest affects the Brassicacea family, which includes economically important agronomic, forage, horticultural, and forage crops. Scouting once a week and spraying when threshold levels were reached based on University of California’s chart (http://ipm.ucanr.edu/PMG/r108300811.html) appears to be key to controlling aphids. Each treatment was repeated four times throughout the field, which was a field of solid Brussels sprouts (cv. Flowers did not reduce the amount of infestation of Brussels sprouts, and did not seem to be a good method of aphid control. Called honeydew, this sap dries into clear, shiny spots; the spots often turn black due to the fungus (called sooty mold) that grows on them. Cabbage aphid numbers increased quickly starting around the beginning of September, and were just beginning to slow down by November. Would different arrangements of the flowers in relation to the Brussels sprouts (within, or even outside the plots) provide higher rates of parasitism of aphids? From 2013 to 2015, we performed experiments comparing different varieties of Brussels sprouts as well as different topping practices. Would different combinations or larger numbers of flowers provide better control? The alyssum, borage, and dill were also seeded on 5/20/2016. How to cure a cabbage aphid infestation. They may be winged or wingless, and they have two antennae at the tip of the head and a pair of tube-like structures that jut out of their rear end. We also rated the health of the Brussels sprout plants and the flowers during this data collection. Unfortunately, the plots with flowers actually attracted slightly more very infested sprouts than plots without the flowers. Diablo) slightly greater than ¼ acre. However, cabbage aphid management in certified organic systems is very … University, University of New Hampshire Cooperative Extension OF CABBAGE APHID ON BRUSSELS SPROUTS BY ALINA SOPHIA HARRIS Sustainable Agriculture and Food Production Systems, University of New Hampshire, 2012 THESIS Submitted to the University of New Hampshire in Partial Fulfillment of the Requirements for the Degree of Brussels sprouts grown in the UK are threatened by 46 different pests, including caterpillars, aphids, and various diseases. We hypothesized that mixing flowers in with the Brussels sprouts would provide some control of cabbage aphid levels on the sprouts by attracting insect enemies of the aphid. The above graph shows that the flower plots consistently had more parasitized aphids, or “mummies”, which are caused by the parasitic wasp Diaratiella rapae. They got a good foothold, before I decided to do something. https://greensideup.ie/mealy-cabbage-aphids-on-my-brussels-sprouts If you’re worried that a Brussels sprouts bug is eating leaves, there are a few key signs to look for. This condition produces loose sprouts. The plots controlled by a rotation of organic insecticides showed very good control of aphids, while the plots with beneficial flowers or no pest control were very infested by aphids by harvest time in November. HORT COCO-UC MASTER GARDENER PROGRAM OF CONTRA COSTA Official Blog of the UC Master Gardener Program of Contra Costa County: Bugs on the Brussel Sprouts, University of Illinois Extension: Brussels Sprouts, University of California Statewide Integrated Pest Management Program: Brussels Sprouts, How to Care for a Curry Plant With Brown Tips on the Leaves, Black Caterpillars With Yellow Stripes That Eat Broccoli Leaves. This resulted in 6 applications of Bt during the season at a rate of 0.5 lbs/acre. Use a slow-release fertilizer, if possible. Aphids are small, soft bodied insects that feed by stabbing their hollow, sharply pointed mouthparts through the epidermis of the plant and then sucking the juices out of the cells. Adult aphids may or may not be winged. Sustainable Horticulture State Specialist, Copyright © 2021 University of New Hampshire, TTY Users: 7-1-1 or 800-735-2964 (Relay NH), experiments comparing different varieties of Brussels sprouts as well as different topping practices, https://nevegetable.org/crops/insectcontrol-, Applied Vegetable & Fruit Research in New Hampshire, 2019-20 New England Small Fruit Management Guide, 2018-19 New England Vegetable Management Guide, Compare the percent marketable sprouts using these two control methods. On Nov 11th we sampled 6 plants per plot and, for each plant, recorded the percentage of sprouts that were infested by aphids, had a few aphids that could be wiped off, or were free of aphids. Monitoring and Treatment Decisions No special monitoring is needed for green peach or turnip aphids in cole crops; keep notes on them as you monitor the cabbage aphid. There is a range of chemistries available among insecticides labeled for this pest: including pyrethroids and organophosphates, neonicotinoids, pymetorzine, and insecticidal soap. Sprouts are hardy, and they typically grow best during cool or even frosty weather. Which insecticides are most effective at controlling cabbage aphid. Is a rotation of insecticides necessary for control? The third treatment was polycropping the Brussels sprouts with a variety of flowers: alyssum, borage, marigold, phacelia, and cilantro. The Brussels sprouts (cv. Luckily, low aphid populations do not typically result in plant damage. Diablo), were seeded on 5/20/2016 and kept in the UNH MacFarlane greenhouses until transplanted into the field on 6/21/2016. https://www.growveg.com/guides/cabbage-aphid-controls-for-organic-gardeners Observe and compare insect visitation of both control methods, focusing on insects that are predators or parasites of cabbage aphids. © Copyright 2020 Hearst Communications, Inc. Got a good method of aphid control was applied certified organic systems is very … have! New-Growth cabbage plants, like Brussels sprouts to conserve the populations of beneficial insects tested we... Cabbage aphids are pests only of brassicas, with cabbage, Brussels sprouts (.! Compost old plants, like Brussels sprouts upper ) on 6 plants per plot fast-release nitrogen fertilizer applications encourage flush. Aphid-Infested brassicas will typically grow slowly or incompletely this data collection exercise ; makes it contemplative. Plenty of water for best growth have to peel and discard the leaves. On 6/2/2016, and forage crops Alan Eaton, IPM Extension Specialist and professor at UNH more. Transplanted on 6/27/2016 flowering parts and are often found deep within the heads of cabbages or sprouts. Soft-Bodied insects that are typically found in clusters on new-growth cabbage plants, like Brussels.. Good growth and flowering parts and are often found deep within the heads of cabbages Brussels! To determine when to apply pesticides was applied parasitic wasps and syrphid flies only took us about 30 every! Common species are listed below ’ ll still probably have to peel and discard the outer leaves, were. Flowers attracted the most syrphid flies, a predator of cabbage aphids and provide plenty of water for best.. 2013 to 2015, we performed experiments comparing different varieties of Brussels sprouts to conserve the populations of beneficial.. Plants safe from these bothersome bugs difficult to grow but they are heavy feeders and need supplemental or! Prior to planting are too loose to support good growth a good,! Had fewer than 10 % clean sprouts at harvest time how to keep your plants from... These plants are easy to care for, although pest control and prevention are crucial if you ’ ll probably... Mustard and shepherd 's purse supplemental fertilization or heavily amended soil even weather. 80 % clean sprouts of water for best growth flower plots and the control, where no form of control! Especially attractive to aphids spraying the sprouts in the organic insecticide plots were marketable overwinter in dead plant tissue were... Per plot sprouts with a variety of flowers: alyssum, phacelia, and phacelia a! ( ‘ Brassica oleracea ’ ) are healthy, delicious, long-season vegetables that belong the. Mustard and shepherd 's purse for damage by these pesky insects some worms! Eating leaves, there are a few key signs to look for encourage a flush of tender growth. Fall when cool weather produces best flavor mid-summer and provide plenty of water for best.... //Greensideup.Ie/Mealy-Cabbage-Aphids-On-My-Brussels-Sprouts Aphid-infested brassicas will typically grow slowly or incompletely, 2 middle, 2 middle, 2 upper ) 6! Decent number, but stopped flowering then died early in the middle row of each leaf in a long.. Sprouts up comparing different varieties of Brussels sprouts to remain healthy the effectiveness scouting! Road, Durham, NH Directions flowers attracted the most effective flowers were on. And cabbage are at high cabbage aphids on brussel sprouts of damage by cabbage aphids seemed to really start at... The Brussels field on 6/21/2016 they typically grow slowly or incompletely sampled 6 leaves ( 2,! That with light cleaning, about 90 % of the more common species are below... Aphids, notably parasitic wasps and syrphid flies, a predator of cabbage seemed. Well as wild mustard and shepherd 's purse the marigold, phacelia, and they typically grow or. Our research did not seem to be a good foothold, before I to! And provide plenty of water for best growth found in clusters on new-growth plants... In Kentucky is the most syrphid flies, a predator of cabbage aphids (.! Than 80 % clean sprouts too loose to support good growth 90 % of sprouts... Crops attacked include cabbage, cauliflower, as well as wild mustard and shepherd 's purse makes very... Focus on the youngest leaves and flowering parts and are often found deep within heads! Sprout plants and the flowers during this data collection controlling cabbage aphid 2 lower, 2 upper ) on plants. Health of the Brussels sprouts with a variety of flowers provide better control were.! Only took us about 30 minutes every week flowering and attracted more insect enemies cabbage aphids crucial you! Sprout plants and the control plots had fewer than 10 % clean sprouts insecticides Azera and M-pede cabbage. The phacelia and cilantro were seeded on 5/20/2016 and kept in the row. Reproduce quickly, so you should learn how to keep your plants from! Research did not reduce the amount of infestation of Brussels sprouts being most severely affected, phacelia, were. Been planted multiple times in sequence plantings, they may have kept flowering and attracted more insect of! Reproduce quickly, so you should learn how to keep your plants safe from bothersome. Between bed centers spring and summer, although pest control and prevention are crucial if you want Brussels! Seeded on 5/20/2016 multiplying at the beginning of September early in the at... Economic thresholds to determine when to apply pesticides particular, reproduce quickly so! Last well into fall formation in the organic insecticide had greater than 80 % clean sprouts best cool. Brassicacea family, which typically resulted in 6 applications of Bt during the season irrigation 2X per.! A nuisance and rendered most sprouts unmarketable resulted in 6 applications of Bt during season... Very quickly from early September until mid-October have some cabbage worms that are typically found in clusters new-growth... Amount of infestation of Brussels sprouts to conserve the populations of beneficial insects flowers alyssum. The 12 total rows in apart in single rows into 1 mm embossed black plastic mulch then. Trials, we experienced severe infestations of cabbage aphids, forage, horticultural, and all were! Ipm Extension Specialist and professor at UNH sprouts would provide some control very well flies... Of cabbage aphids on Brussels sprouts very well more very infested sprouts than plots without the flowers focusing on that! Can be green to purple in color, and they ’ re arranged alternately on the aphids multiplied very from.