Sustainable, OrganicVegetable GardeningPresented by: Kent Phillipskent.a.phillips@gmail.com

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Maryland Master GardenersMission

To educate Maryland residents about safe, effective and sustainable horticultural practices that build healthy gardens, landscapes, and communities.

www.extension.umd.edu/growitGrow Your Own FoodWe Can Show You HowClick on Classes TabAnd Scroll down to Howard County

Reduce Your Carbon Footprintby Vegetable GardeningLess trips to the storeSequester carbon in your vegetable bedsHealthy plants capture carbonCreate compost Put it back in your bedsBetter tasting vegetables*

We teach a common-sense, ecological approachRely on local materials and resources Compost neighbors leaves and your grassLocal animal manureLeafgroMaximize biological and genetic diversity to strengthen your garden eco-system. Example: Plant an assortment of annual flowers and herbs to attract and feed beneficial insects.

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Unbordered raised beds

Ingredients to a Successful Vegetable GardenHealthy soilLots of organic materialProper soil pHProper nutrient levelsNPKSecondary and micro nutrientsSufficient soil moisturePractice Integrated Pests Management (IPM)Grow recommended vegetable varietiesHG 70 Recommended vegetable cultivars for Maryland home gardens

Importance Of These Ingredients Healthy plants resist grow insect attackIPMIn nature, bad insects are predated by beneficialsUse physical controls and erect barriers to pests Use targeted applications for specific pests Use broad spectrum insecticides only as a last resortRecommended vegetables grow

What is Healthy SoilSoil rich in organic matter with lots of invertebratesHas lots of pores for air and water Six inches of OM for new gardensOne inch for established gardensSoil with proper pH and nutrient levelsDo a soil testFollow recommendations

Healthy soil (cont.)References at www.extension.umd.edu/hgic click on Soils or click on Information Library, Publications and Soil, Mulch and CompostingHG11 Soil test basicsHG110 Selecting and using a soil testing laboratoryHG 42 Soil amendments and fertilizersFS782 Basics of soil and plant fertilityhttp://www.youtube.com/UMDHGIC to see video on collecting a soil test sample

Fertilizer RecommendationU of Mass recommendation is .25#s/100 square feet1# of 30-3-330% N, 3% P and 3% K.3#s of N, .03#s of P and .03#s of K4#s of dried blood meal 12-0-012% N, 0% P and 0% K.48#s of N probably too muchLarge amount of N is readily available to plants

Soil MoistureOn average plants require one inch of water a weekOn a 4 by 8 foot bed, thats 20 gallons of waterMoisture needs to be delivered to the plant rootsMost efficient method of delivery is drip irrigationhttp://www.youtube.com/UMDHGIC look or search for video on Drip IrrigationMulching plants helps conserve soil moisture http://www.youtube.com/UMDHGIC look or search for video called Mulchzilla

Intensive plantingAssume a four foot wide bedIn a 2 or 3 foot long area plant 5 broccoli plants in an x pattern Plant 4 lettuce plants between the broccoli plantsB L B

L B L

B L B

Intensive planting (cont)Plant three row of green beans in a four foot squarePlant four rows of beets or carrots or onions in the same areaPlant tomatoes three feet apart on the north or west side of the gardenPlant peppers and eggplants in the same pattern as broccoli aboveVegetable spacing on Pub HG 16

Succession PlantingUse transplants when possible Cool weather crops (spring and fall)Broccoli, cauliflower, lettuce, etc.Warm season crops (summer)Tomatoes, peppers, eggplants, squash, etc.Rotate cropsPlant beans after broccoli (adds N to soil)Dont plant tomatoes, eggplant or potatoes where they have been before.

Start early, end lateGarden from 4/1 to 12/15See Pub. GE 007 or HG 16 for planting timesCool season crops (Mid March & April)Warm season crops (mid-May & early June)Cool season crops (August & September)Garlic (mid-October)Winter over spinach and kale for spring crop

Integrated Pest ManagementSimple steps and common senseStudySpySquishAn once of prevention is worth a pound of cureCompanion plantingA healthy garden with good soil, adequate moisture and proper nutrition can withstand some pest predation

Beneficials v. PestsAttract predators and parasites by planting open faced flowers which attract predators that require nectar in their adult stageUltimately, predators will increase as prey is availablePurchasing predators tends not to be effectiveDucks, chickens and toads

Common PredatorsPraying Mantid

Common PredatorsLady Bird Beetle and Larva

Common PredatorsYellow ArgiopeJumping spiderWolf SpiderOrb Weaver

Wheel bugCommon Predators

Common PredatorsSyrphid fly and larva: predator of aphids

Common PredatorsParasitized Tomato Hornworm

Common Vegetable PestsMexican Bean BeetleAdultEggs & larvaeRow coverCrushPyrethrum, neem, spinosad spray top and bottom of leaves

Common Vegetable PestsCucumber BeetleStrippedSpottedFloating row coverPyrethrum, neem oil, spinosad

Common Vegetable PestsHarlequin bugAdultEggs & nymphsRow coverCrushInsecticidal soap alone or with pyrethrum or neem

Common Vegetable PestsFlea BeetleAdultsFloating row cover over hoopsSurround (kaolin clay) reapply after rainPyrethrum, neem, spinosad

Common Vegetable PestsImported Cabbage LooperAdultLarvaeFloating row coverBacillus Thuringensis (BT), insecticidal soapPyrethrum, neem, spinosad use with sticker spreader

Common Vegetable PestsSquash BugAdultEggs & nymphsNo pesticide for homeownersFloating row coverHand pick tear out section of leaf with eggsKill nymphs with neem or hort oil or insecticidal soap

Common Vegetable PestsSquash Vine BoreLarvaeFloating row coverCut out borer and mound soil over wound

Common Vegetable PestsStink BugsBMSB AdultSouthern Green Stink BugBrownTrue hard shell bugs like squash and stink bugs are hard to killUse row cover where possibleHand pick and destroy adults and eggsInsecticidal soap and botanicals can be used on 1st and 2nd instars (nymphs)No pesticide available for homeowners to kill adults

Targeted Applications for Specific PestsWith all pesticidesAlways read the labelFollow label instructionsBacillus ThuringiensisCabbage looper and other caterpillarsHorticultural oilsInsecticidal soap

Broad Spectrum KillersWith all pesticidesAlways read the labelFollow label instructionsPyrethrumsPyganicRotenoneSpinosadNeem oil

ResourcesHome and Garden Information Center (HGIC)800-342-2507http://www.extension.umd.edu/hgicGrow-It-Eat-It websitehttp://www.extension.umd.edu/growitYouTube - Search subjecthttp://www.youtube.com/UMDHGIC

This program was brought to you by Maryland Master Gardener ProgramHoward CountyUniversity of Maryland Extension

You can edit your own title, sub title, author and email.*Register your garden large or small - on the GIEI Website address on a later slide.**We dont want to get too hung up on labels. We could substitute organic and sustainable for ecological.

Rocks from your yard can form the sides of a raised bed or you can just rake the bed into a mound; leaves from neighborhood trees can be shredded and added to the garden to improve soil quality and plant growth. Why buy dried steer manure from out west when there are locally available sources. You can find locally available cow, horse or sheep manure but make sure it has been composted or it will contain weed seeds. Also, fresh manure contains lots of nitrogen and can burn plants if it has not been composted.

Feed the soil and the soil will feed the plants. Soil fertility is one of the most important factors in creating a successful vegetable garden and is accomplished by adding organic matter to the garden. OM improves the structure of the soil so that its easier to work with, holds water and nutrients and improves root growth. Leafgro is a commercial product made from leaves and produced by Maryland Environmental Services. It is fairly inexpensive in bulk quantities ($20 per yard) if you have the means to transport it. When starting a new garden, six inches of compost should be worked into the soil. A yard of leafgro would cover an 54 square foot garden to a depth of six inches.

3.Diversity is another key to success. Different types of organic matter added to the soil will increase the diversity of critters in the soil. This ultimately benefits plant growth.

What is a Sustainable Garden:Sustains itself through reliance on inherent resources; mimics natural eco-system.Needs a minimum of purchased inputs and relies on locally-available materials. Its not sustainable to buy compost or chicken manure from 5 states away when we have plenty locally.Builds soil health (feeding the soil food web and recycling nutrients). Also, keep the soil covered (when you are not tilling or turning) with plants, mulch, cover crop, leaves, etc.Increases biological diversity above and below ground- plants, insects, microbial lifeDoes not pollute; strengthens the community eco-system. Requires knowledge, planning, and timing.There is no need to use chemical insecticides, herbicides, or fungicides in a vegetable garden.

What is Organic Gardening: no chemical fertilizer or pesticide. No rules (list of allowed and not allowed materials) for gardeners- just for farmers who are part of the National Organic Program. More info on organic gardening and farming and a list of certified organic farmers in MD is on the GE web site. Organic doesnt mean simply substituting purchased organic pesticides and fertilizers for synthetic products.

Diversity of plants also benefits the garden. For example, planting herbs and open faced flowers like zinnias, Queen Annes lace or cosmos attract beneficial insects which prey on bad bugs. *These beds are four feet wide and I have four foot grass walkways between the beds.*There are four main keys to maintaining a healthy vegetable garden. Well discuss each in turn.

*Using this approach, you can grow great vegetables with a minimal amount of pesticide. Is it more labor intensive, yes. But once you build up your soil, the work will become much easier.

*Most important is healthy soil. So what do I mean when I say healthy soil. First, healthy soil has lot of organic material incorporated into it and supports a diverse population of invertebrates and microbes. Older established gardens should have about one inch of compost added each year. New gardens should have six inches of organic material added in the first year. For a 4 by 25 foot bed, thats almost 2 yards of compost 100 sq. ft. times half a foot = 50 cu ft. or almost 2 yards. Second, soil must be in the proper pH range generally 6.2 6.8 for vegetables. Soils that falls outside of this range will need to be brought back into range using either lime to raise the pH of sulfur to lower the pH (a problem we in MD dont generally have).Third, soils need to contain the proper nutrients for plant growth. The macro nutrients are nitrogen (N), phosphorus (P) and potassium (K). In general, we add fertilizers to increase the availability of these macro nutrients. Secondary and micro nutrients are also important. They include calcium, magnesium, sulfur, iron, manganese, boron, molybdenum, copper, zinc and chlorine.There is only one sure way to determine the soils pH level and the availability of nutrients and that to take a soil test and send it to a lab. Soil tests are cheap and yield great information on the fertility of your soil.

Vegetables grow in soils with a pH between 6.2 and 6.8. Optimal pH depends on type of vegetable being grown, but a good pH for an all around vegetable garden is 6.5. pH is raised by adding lime to the soil. Recommendations for liming are generally given in pounds of lime per 1,000 square feet. Normally, the maximum amount of lime that can be applied in one application is 50# although 70# can be applied if the lime is being incorporated into the soil.

Maryland soils tend to be high in phosphorous so normally, only N and K need to be added. If your soil has had lots of OM incorporated into it, you may not need additional NPK otherwise,HG#42 recommends addition .1-.2#N , and .2-.4#pk / 100 for new gardens. For established gardens, the recommendation is for .2#n, .12#P and .08#K/100.Talk about NPK conversion using blood meal as an example. Its 10-12%N so to fertilize and established garden you divide .2#n by 10% to yield 2# blood meal per 100 sq. ft.

After you receive your soil test, you can refer to Home and Garden pub 42 entitled soil amendments and fertilizers. While organic gardeners can use organic forms of NPK, the basic rules of applying these amendments remain the same.

Most important, stay off your soil and dont compact it. This is especially true when the soil is wet. Almost as important is dont over till your soil. Tilling once a year to incorporate compost and soil amendments is sufficient. Repeated tilling introduces added oxygen into the soil and tends to cause accelerated decomposition of the organic material releasing CO2 into the atmosphere.*This soil test is from one of my vegetable beds. Notice that all of my macro nutrient levels are very high as a result of years of fertilization with 10-10-10 and use of large quantities of compost. pH levels are also near neutral because of liming and the use of compost which has a pH of 7.0.The Univ. of Mass. recommends using a fertilizer which is mostly N. Last year, I used soybean meal (an organic, slow release fertilizer,) which has a NPK of 7-3-1 or 7% N. I spread 3.6 lbs. of soybean meal per 100 square feet of garden.

Because all of the numbers in the NPK formula are percentages, its easy to calculate the amount N you need for 100 square feet. Simply take the N number from the bag of fertilizer from the bag and divide it into the recommendation, here .25. *The second key to a healthy vegetable garden is maintaining sufficient soil moisture at the plants root level. In general, plants require about one inch of water a week to maintain healthy growth. Thats .62 gallons per sq.. or 62 gallons per 100. While rain supplies the bulk of this water to most gardens, during our hot dry summers, rain is tends to be absent and we have to find alternatives. Most gardener just hose down there gardens, but this method of watering is very wasteful since most of the water runs off and never reaches the root zone.

The preferred method of supplying moisture to the roots is drip irrigation. While there are low tech solutions, such as using bucket and 2 liter bottles sunk in the ground, high tech systems are relatively inexpensive and reusable year after year. A drip irrigation system for a 20 by 25 foot garden would cost about $80 initially with about $12 annually for new drip tube. I have helped install several drip system in the community gardens. They generally increase vegetable production by 100%.

Mulching plants during the summer also helps conserve moisture. Mulch can either be organic (compost, etc.) or inorganic (plastic). Drip irrigation under mulches are especially effective at keeping moisture in the plants root zone.*The second key to a healthy vegetable garden is maintaining sufficient soil moisture at the plants root level. In general, plants require about one inch of water a week to maintain healthy growth. Thats .62 gallons per sq.. or 62 gallons per 100. While rain supplies the bulk of this water to most gardens, during our hot dry summers, rain is tends to be absent and we have to find alternatives. Most gardener just hose down there gardens, but this method of watering is very wasteful since most of the water runs off and never reaches the root zone.

The preferred method of supplying moisture to the roots is drip irrigation. While there are low tech solutions, such as using bucket and 2 liter bottles sunk in the ground, high tech systems are relatively inexpensive and reusable year after year. A drip irrigation system for a 20 by 25 foot garden would cost about $80 initially with about $12 annually for new drip tube. I have helped install several drip system in the community gardens. They generally increase vegetable production by 100%.

Mulching plants during the summer also helps conserve moisture. Mulch can either be organic (compost, etc.) or inorganic (plastic). Drip irrigation under mulches are especially effective at keeping moisture in the plants root zone.*Third, we need to keep pests to acceptable levels. Notice I didnt say eliminate pests. Bugs are a common occurrence in gardens and most healthy gardens can withstand some intrusion by pests. IPM is a method for keeping pests at a acceptable level.

IPM: simple steps and common senseStudyRight plant in the right place; give them what they need.Know the important pest problems and how to prevent them. Bean beetles on beans, flea beetles on eggplant, Colorado potato beetle on potatoes, etc.Learn the habits, life-cycle, and weaknesses of key pests.

SpyMonitor plants closely for signs and symptoms of problems. Monitor your garden at least once a week to catch problems early to avoid their spread. Are symptoms getting worse? Strive for correct diagnosis of problem. Use a magnifying glass on small pests.

SquishTake least toxic action. Pick off large pests and either squish them or drop them in a pail of soapy water. When possible use a barrier to deter pests from attacking the plant. (well talk more about this later)Specific vs. all-purpose treatment. Each plant has specific insect pest(s) no need to broadcast an all-purpose killer E.g.. Use BT for caterpillars rather than a broad spectrum pesticide.Monitor your treatment. Did the it work? Continue to monitor.Prevention - In taking preventive measures youre working with nature to prevent an outbreak instead of dealing with problem after it gains a foothold in your garden. But for prevention to work most effectively, you need to detect pests early, determine the extent of the infestation and take action to keep pests at acceptable levels.

You can also use companion planting to deter some common garden pests. There are many websites that have extensive lists of plants that make good companions. Some plants help repel bugs, while others act as a magnet and can be used to trap unwanted pests.

*Attract beneficials (pest parasites and predators)A garden insectary is a small garden plot of flowering plants designed to attract and harbor beneficial insects. These "good insects" prey on many common garden insect pests Intersperse vegetable beds with rows or islands of insectary annuals. Allow some of your salad and cabbage crops to bloom. Include plants of different heights in your insectary. Tiny flowers produced in large quantity are much more valuable than a single, large bloom. Small shallow flowers easer to extract nectarAttractant plants should be very detectable and predictable (perennial island provides overwintering site)

Some good plants for holding beneficials are:Mint (anise hyssop, thyme)Carrot (dill, yarrow)Aster (tansy, marigold, zinnia)Brassica (alyssum, dames rocket, Asian greens)Buying and releasing predators and parasitesNot generally recommended because they tend to disperse; effectiveness variesOk for severe spider mites infestations All Hail to the Predators spiders

*Fall greens protected with floating row cover draped over wire hoops and secured to the ground with tomato stakes.*Floating row cover over pvc hoops to protect fall broccoli and cabbage and cauliflower from pests and to accelerate growth.*As with all pesticides, Its very important to read the label. Not only will the label tell you what insects the pesticide is effective against but it will also give information on dilution rates and methods of application. Always follow label instructions.

BT should be sprayed once you start seeing cabbage moths around your plants. I personally prefer to cover my brassics with row cover during early growth and catch the cabbage moths in a butterfly net with my grandson as the broccoli matures. I only use BT when the infestation gets out of control.

Oils remain an important tool to manage certain pest problems (e.g., scales, aphids, mites) on fruit trees, shade trees and woody ornamental plants. Several recently developed oils extend this usefulness to flowers, vegetables and other herbaceous plants. Oils also can control some plant diseases, such as powdery mildew. Oils used to protect plants have been called by many names, but perhaps horticultural oils best describes them.Oils have different effects on pest insects. The most important is that they block the air holes (spiracles) through which insects breathe, causing them to die from asphyxiation. In some cases, oils also may act as poisons, interacting with the fatty acids of the insect and interfering with normal metabolism. Oils also may disrupt how an insect feeds, a feature that is particularly important in the transmission of some plant viruses by aphids.Oils pose few risks to people or to most desirable species, including beneficial natural enemies of insect pests. This allows oils to integrate well with biological controls. Toxicity is minimal, at least compared to alternative pesticides, and oils quickly dissipate through evaporation, leaving little residue. Oils also are easy to apply with existing spray equipment and can be mixed with many other pesticides to extend their performance.The main limitation of spray oils is their small but real potential to cause plant injury (phytotoxicity) in some situations.

How soaps and detergents kill insects is still poorly understood. In most cases, control results from disruption of the cell membranes of the insect. Soaps and detergents may also remove the protective waxes that cover the insect, causing death through excess loss of water.Soap-Detergent SpraysSoaps and detergents act strictly as contact insecticides, with no residual effect. To be effective, sprays must be applied directly to and thoroughly cover the insect.Several insecticidal soaps are distributed for control of insects and mites. Available under a variety of trade names, the active ingredient of all is potassium salt of fatty acids. Soaps are chemically similar to liquid hand soaps. However, there are many features of commercial insecticidal soap products that distinguish them from the dishwashing liquids or soaps that are sometimes substituted. Insecticidal soaps sold for control of insects: are selected to control insects; are selected to minimize potential plant injury; and are of consistent manufacture.Some household soaps and detergents also make effective insecticides. In particular, certain brands of hand soaps and liquid dishwashing detergents can be effective for this purpose. They are also substantially less expensive. However, there is increased risk of plant injury with these products. They are not designed for use on plants. Dry dish soaps and all clothes-washing detergents are too harsh to be used on plants. Also, many soaps and detergents are poor insecticides. Identifying safe and effective soap-detergent combinations for insect control requires experimentation. Regardless of what product is used, soap-detergent sprays are always applied diluted with water, typically at a concentration of around 2 to 3 percent (Table 1).Susceptible InsectsMost research with insecticidal soaps and detergents has involved control of plant pests. In general, these sprays are effective against most small, soft-bodied arthropods, such as aphids, young scales, whiteflies, psyllids, mealybugs, and spider mites. Larger insects, such as caterpillars, sawflies and beetle larvae, generally are immune to soap sprays. However, a few large insects, including boxelder bugs and Japanese beetles, are susceptible. Colorado State University Extension. 12/96. *As with all pesticides, Its very important to read the label. Not only will the label tell you what insects the pesticide is effective against but it will also give information on dilution rates and methods of application. Always follow label instructions.

How pyrethins works: Pyrethrum is a fast acting contact poison that knocks down susceptible insects. Insects are left paralyzed by the toxic effect of pyrethrum. The normal function of the nervous system is affected, stimulating repetitive nerve discharges leading to paralysis. However, some insects are able to recover after the initial knockdown if the dose is too low. Stink bugs appear to fall into this category.Warning, there is also a synthetic pyrethroid on the market but it is not labeled organic.

How Rotenone works: Rotenone is a slow-acting poison which interferes with the electron-transport system in the mitochondria. It acts as both a contact and stomach poison.Types of pests it controls: Rotenone is an excellent organic pesticide dust for the garden. It kills potato beetles, cucumber beetles, flea beetles, cabbage worms, raspberry bugs, and asparagus bugs to name a few. Rotenone bio-degrades naturally in a few days so there is no harmful residue. A light dusting on the leaves of plants will control insects for several days. It is not harmful to humans when used properly. Rotenone is toxic to many species of insects in many different insect orders (caterpillars, beetles, flies, etc.). It also kills fish and ticks.

Spinosad was developed in the mid-1990s. Its a secondary metabolite from the aerobic fermentation of Sacharopolyspora spinosa (a naturally occurring soil microorganism). Spinosad is a nerve and stomach poison and must be ingested to kill insects. Paralysis and death occur within minutes although insects may remain on the plant for up to two days. Spinosad has limited translaminar activity, meaning it can move somewhat into leaf tissue. This makes it effective against leafminers that feed within leaves. It has very low toxicity to non-target organisms including pollinators and other beneficial insects.Spinosad will control: caterpillars (e.g. armyworms, European corn borer, cabbageworm, corn earworm, cutworms, hornworm) and borers, thrips, leafminers, sawflies, Colorado potato beetle. Less effective on beetles and not effective against sucking insect pests such as bugs and aphids. Products: Monterey Garden Insect Spray - 16 Oz. Concentrate Bonide Captain Jacks Deadbug Brew Ready to Spray .5% Bonide Colorado Potato Beetle Beater- Concentrate .5% Gardens Alive- Bulls-Eye (http://www.gardensalive.com)How to use:Only a small amount per gallon is required- about 4 tablespoons per gallon of water). Its very important not to spray spinosad more than 23 times per growing season to reduce the risk of pests developing resistance to the active ingredients. Organic farmers alternate spinosad with B.t. for controlling caterpillar pests.

How Neem oil works: Pesticide active ingredients are based on neem seed extracts, including azadirachtin, neem oil and neem oil soap. Azadirachtin, one of the more than 70 compounds produced by the neem tree, acts mainly as an insect growth regulator, but also has anti-feedant and oviposition (egg-laying) deterrent properties. First isolated in 1968, azadirachtin is thought to be the most bioactive ingredient found in the neem tree; however, such speculation may be due to it having been investigated more thoroughly then the other compounds (Thacker 2002, Quarles 1994). Most commercially available neem products list azadirachtin as the primary active ingredient. Such products are broad-spectrum insecticides, which work by contact or ingestion. As an insect growth regulator, azadirachtin prevents insects from molting by inhibiting production of ecdysone, an insect hormone. Azadirachtin is chemically similar to ecdysonlids, the hormones responsible for triggering molts (Weinzierl and Henn 1991). As an anti-feedant it may cause an insect to stop feeding after ingestion due to secondary physiological effects. As an egg-laying deterrent, volatile compounds from neem may repel some insects from depositing eggs on a plant surface.

A recent study compared the effectiveness of a rotenone-pyrethrin mixture versus a synthetic pesticide, imidan. Rotenone and pyrethrin are two common organic pesticides; imidan is considered a "soft" synthetic pesticide (i.e., designed to have a brief lifetime after application, and other traits that minimize unwanted effects). It was found that up to 7 applications of the rotenone- pyrethrin mixture were required to obtain the level of protection provided by 2 applications of imidan. It seems unlikely that 7 applications of rotenone and pyrethrin are really better for the environment than 2 applications of imidan, especially when rotenone is extremely toxic to fish and other aquatic life. It should be noted, however, that we don't know for certain which system is more harmful. This is because we do not look at organic pesticides the same way that we look at conventional pesticides. We don't know how long these organic pesticides persist in the environment, or the full extent of their effects.

**Remember to put in the correct county!*