Intensive Vegetable Productionon a Small Scale©Pam Dawling 2013

Twin Oaks Community, Central Virginia

Author of Sustainable Market FarmingPublished by New Society Publishers

SustainableMarketFarming.com facebook.com/SustainableMarketFarming

Starting Your Plants Photo Kathryn Simmons

• Choose high-yielding varieties suited to your climate, budget, certification and market (smooth or savoyed? OPs or hybrids?)

• Buy seeds or starts? Is what you want available as plants? Do you need Organic? Is the price worthwhile? Money vs labor.

• Direct sowing or transplanting? Do you have the equipment to grow transplants? (germination chamber, greenhouse, heat)

Direct SeedingPhoto Kathryn Simmons

• Pros– Less work– Better drought tolerance – roots

grow without damage– Some crops don’t transplant easily– Some crops have millions of

plants! (Carrots)• Cons

– Uses more seed, more money– Occupies the land longer– Maybe harder to get started in

cold (or hot) conditions

Getting the best from direct sowing Viable seed, not too old Good soil conditions lead to even

germination: tilth (size of particles), moisture

Decide by soil temperature, not calendar. New Seed Starter’s Handbook.

Correct depth and sowing density Good seed contact with soil: tamp lightly Good tools: Earthway, precision seeders,

hoes, jab planters for large seeds, tractor seed drills.

• Photo Bridget Aleshire

TransplantingPros

– Can start seed in more ideal conditions in greenhouse, better germination, more fun!

– Can start earlier than outside, get earlier harvests– Easier to care for new seedlings in a greenhouse– Protected plants grow quicker – Can select sturdiest plants, compost the rest– More flexibility if weather turns bad. Plants still

grow!– Fit more crops into the season– Use time windows for quick cover crops– Save on seed costs

Cons– Need to plan and schedule

Photo Kathryn Simmons

Getting the best from transplanting Open flats, plug trays, soil blocks, bare root plants. Roots need space. Transplant shock is less for plants with plentiful root systems, and harvest starts

sooner. Seed compost: fine texture, enough nutrients, good water-holding and drainage

capacity. Good pH, enough P Use a soil thermometer, not a calendar, to decide when to plant out tender

plants. At 65°F (19°C), tomatoes and sweet potatoes can be planted. 70°F (21°C) is better for peppers and melons. Don’t rush!

Measure and mark the correct spacing: tractor equipment, rolling dibbles, row marker rake, measuring sticks and triangles, width of the hand, span of finger and thumb.

Ideal conditions for transplanting are mild windless afternoons and evenings just before (or during!) light steady rain.

Transplanting late in the day gives the plant the chance to recover during the cooler night hours when the rate water loss is slower.

Shadecloth or rowcover can be used to reduce the drying effects of wind and sun. Don’t assume they’ll make it hotter!

Hardening off (or not)• Most starts need to be hardened off before planting out in the field. • Move the plants to a transitional zone - a coldframe or a shade house, with

conditions midway between outdoors and the greenhouse. • Hardening off requires lower temperatures (for most crops) with greater

fluctuations, more breezes and more direct sunlight. • Less watering can be part of hardening off, (but not for brassicas, lettuce). • Avoid sudden changes, as stress may cause permanent damage. • Plants respond by reducing the size and number of their stomata and by

developing a sturdier stem, a thicker leaf, perhaps with a wax coating. • Slower growth causes the plants to store carbohydrates, which feed

regrowth after transplanting. • Move the plants out to the coldframe when weather conditions are mild,

and use lids or rowcovers to moderate the microclimate for the first several days.

• Or keep the plants on a cart and move it outside in the daytime, in at night.

Transplant age and sizeVegetable Notes Ideal Age at TransplantingCucumbers,

melons,squash 2 true leaves max (maybe less) 3–4 weeks

Watermelons (older is OK) 3–4 weeks

Sweet Corn 3–4 weeks

Tomatoes age is less important 4–8 weeks

Lettuce 4–7 weeks

Brassicas 5 true leaves is ideal 6–8 weeks spring/3–4 weeks summer

Peppers & eggplant 4 or 5 true leaves, not yet flowering 6–8 weeks

Onions (spring sown) & leeks 10–12 weeks

Celery 10–12 weeks

Transplanting deptho Deeper planting seems to reduce wind stress on

young plants. o Plant to the depth of the first true leaves -

increases yields of many crops. Often this is deeper than the plant was in the flat.

o Some plants (tomatoes) grow extra roots along the buried stem.

o But, soil is cooler deeper down, and this may not be a good thing for warm-weather plants. e.g. sweet potatoes and tomatoes

o So - plant in a shallow horizontal or diagonal trench. Bury much of the stem in the soil, increasing the growth of extra roots and protecting the plant against wind damage, while keeping the roots in the warmer soil near the surface.

Photo Kathryn Simmons

Water is Vital for Transplants! Damp soil is important before, during and after

transplanting. Water your plants an hour before transplanting, and then also well after planting. If necessary, in very dry weather, water the field ahead of planting, either with overhead sprinklers or drip irrigation right on the planting row. Set out drip tape with emitters at the chosen crop spacing, water for twenty minutes before planting, and then plant directly into the wet spots. No other measuring is needed.

When setting out a large number of plants, I recommend most people water every twenty to thirty minutes, regardless of the number of plants set out.

Water the transplants the next day, on days three, seven and ten after planting, and then weekly after that.

Photo credit Luke Stovall

Irrigation – which method?Overhead Sprinklers

• cheap to buy• easier to understand • in some circumstances they do a

better job, for instance when you need to water in a broadcast cover crop or closely drilled rows

• can help cool crops in hot weather

• can help prevent frost damage• Can run overnight• Use less plastics

Drip irrigation• Greatly reduces the amount of

water used • waters only the crop, not the

weeds between the rows• Reduces likelihood of foliar

diseases in dryish climates• can run on timers• Once set up, less gear to move

before watering• Can water large areas at once• can be used to mark spots for

transplants• Tape can be wound up and re-

used• Old tape can be used to batten

hoophouse plastic

Crop Spacing Goals Yield is related to plant density. Balance point at

which the plant density provides the maximum total yield. Some plants will be too small to use, that’s taken into account when calculating yield.

Area per plant is the important bit, not particular row spacing.

Crop size (do customers want big carrots or small carrots?)

Disease control (humidity and molds) Preferred layout (beds with equidistant plants, or

rows). For large plants such as okra or eggplant, it makes more sense to plant a single row in a bed and have the plants close together in that row, forming a “hedge.” It is easier to cultivate plants that are 2 feet (60 cm) apart in 5-foot (150-cm) rows than plants at an equal spacing of 30 inches (76 cm) in all directions — an eggplant jungle!

Ease of cultivation (tractor equipment, hoes, horses) and irrigation

Photo of Morris Heading Collards by Kathryn Simmons

Optimal Crop Spacing for Various GoalsCrop Row spacing In-row spacing NotesBeets 7" (18 cm) 4" (10 cm) For early harvest

12" (30 cm) 1" (2.5 cm) For max total yield (small). 2" (5 cm) for bigger beets

Beans, fava 18" (45 cm) 4.5" (11 cm) For tall varieties.Beans, green 18" (45 cm) 2" (5 cm) 12" (30cm) × 3" (7.5 cm) gives the same area/plantBroccoli (Calabrese) 12" (30cm) 6" (15 cm) For equal amounts of heads and side shootsCabbage 14" (35 cm) 14" (35 cm) For small heads

18" (45 cm) 18" (45 cm) For large headsCarrots 6" (15 cm) 4" (10 cm) For early crops, limiting competition

6" (15 cm) 1.5" (4 cm) For maincrop, medium size rootsCelery 11" (28 cm) 11" (28 cm) For high yields and mutual blanchingCucumber (pickling) 20" (51 cm) 3" (8 cm)Leeks 12" (30 cm) 6" (15 cm) Max yield of hilled up leeks, average sizeLettuce 9" (23 cm) 8" (20 cm) Early crops under cover

12" (30 cm) 12" (30 cm) Head lettuce5" (13 cm) 1" (2.5 cm) Baby lettuce mix

Onions 12" (30 cm) 1.5" (4 cm) For medium size bulbs12" (30 cm) 0.5" (1 cm) For boiling, pickling, kebabs

Parsnips 12" (30 cm) 6" (15 cm) For high yields of large roots7.5" (19 cm) 3" (8 cm) For smaller roots

Peas, shelling 18" (46 cm) 4.5" (11.5 cm) Can sow in double or triple bands, 4.5" (11.5 cm) apartPotatoes 30" (76 cm) 9-16" (23–41 cm) Depends on size of seed pieces; small pieces closerSweet Corn 30-36" (76–90 cm) 8" (20 cm) Closer than 8" (20 cm) the plants shade each other.Tomatoes, bush types 19" (48 cm) 19" (48 cm) For early cropsWatermelon 66" (168 cm) 12–24" (30–60 cm) For small varieties. 5–10 ft2 (0.5–1 m2) each

66" (168 cm) 30–84" (76–215 cm) For large varieties. 13–40 ft2 (1.2–3.7 m2) each

Biointensive Integrated Pest Management

Four steps of IPM: 1. prevention (reduce chance of problems)2. avoidance, 3. monitoring (is action needed?)4.Suppression (least toxic solution)See the handout for more details

Carrot pest damage photo by Jessie DoyleZipper spider on tomato, photo by Wren Vile

Sustainable Disease Management

Diseases need • a susceptible host, • the presence of a pathogen, • suitable environmental conditions.

Plant pathogens can be • soil-borne, • foliar-borne,• seed-borne, • a combination of seed-borne with one of the others. See the handout for more details of these types and of the Biointensive IPM steps

Bio-intensive Disease IPM1. Cultural controls

(preventative strategies)2. Monitor crops for problems3. When control measures are neededa) Physical controlsb) Biological controlsc) Microbial controlsd) Botanical controlse) Inorganic controls (Also known as

biorational disease controls)See the handout for information on these types of controls

Proteknet on hoops, keeps cucumber beetles out. Dubois Engineering

Sustainable Weed ManagementWeeds compete with crops for sunlight, water and

nutrients, and can encourage fungal diseases by reducing airflow.

Too-frequent cultivation to remove weeds can leave the soil more prone to erosion

Each tilling or deep hoeing stirs air into the soil and speeds combustion of organic matter

Most weeds respond well to nutrients, especially nitrogen. If you give corn too much nitrogen, even as compost, its productivity will max out and the weeds will use the remaining nutrients.

Sustainable weed management is about effectiveness

• Remove weeds at their most vulnerable stage, or at the last minute before the seedpods explode —ignore weeds doing little damage.

• Different types: annuals and perennials; stationary perennials (docks) and invasive perennials (Bermuda grass); cool-weather and warm-weather types; quick-maturing and slow-maturing types; “Big Bang” types (pigweed) versus “Dribblers” (galinsoga, shown here)

• Photo Wren Vile

Methods of sustainable weed control1. Preventing weeds from

germinatingPhoto credit Luke Stovall

2. Reducing weed seeding3. Reducing weed seed viability4. Reducing the strength of perennial weed roots and rhizomesSee the handout for more on these strategies. Photo Brittany Lewis

Season Extension Advantages and disadvantages in time and money Growing earlier crops in spring:

o Fast-maturing hardy varietieso Warm microclimateso Transplantso Rowcovers, low tunnels, Quick Hoops, high tunnels (hoophouses)

Extending the growth of cool-weather crops into summer:o Learn how to germinate seeds in hot weathero Shadeclotho ProtekNet to keep bugs offo Intercropping allows a new crop to establish before the old one finishes

Extending the survival of frost-tender crops beyond the first fall frostso Rowcover returns to the fieldso Minimizing frost damage

Growing cold-hardy winter vegetables

Resources• The Complete Know and Grow Vegetables J. K. A. Bleasdale, P. J. Salter et al.• Knott’s Handbook for Vegetable Growers, Donald N. Maynard and George J. Hochmuth• The New Seed Starter’s Handbook, Nancy Bubel, 1988, Rodale Books• The Organic Farmer’s Business Handbook, Richard Wiswall, 2009, Chelsea Green• Southwest Florida Research and Education Center, swfrec.ifas.ufl.edu/vegetable_hort/transplants.

(Detailed information on age of transplants, container size, biological control for pests, diseases, hardening off, plant size, planting depth and temperature. )

• ATTRA attra.ncat.org Plugs and Transplant Production for Organic Systems, Scheduling Vegetable Plantings for a Continuous Harvest, and Season Extension Techniques for Market Farmers, and many other great publications.

• Sustainable Vegetable Production from Start-up to Market, Vern Grubinger, 1999,• Nature and Properties of Soils, fourteenth edition, Nyle Brady and Ray Weil• Garden Insects of North America, Whitney Cranshaw • Cornell Extension website: vegetablemdonline.ppath.cornell.edu/NewsArticles/All_BactSeed.htm

Good detailed information on seed treatments.• Manage Weeds on Your Farm: A Guide to Ecological Strategies, Chuck Mohler (not yet published)• Extending the Season: Six Strategies for Improving Cash Flow Year-Round on the Market Farm, a free

e-book download for online subscribers to Growing for Market magazine• www. eOrganic.info. The organic agriculture community with eXtension. Publications, webinars,

videos, trainings and support. An expanding, accessible source of reliable information.• http://growingsmallfarms.ces.ncsu.edu/ Debbie Roos keeps this site up to the minute.

Intensive Vegetable Productionon a Small Scale©Pam Dawling 2013

Author of Sustainable Market FarmingPublished by New Society Publishers

SustainableMarketFarming.com facebook.com/SustainableMarketFarming