1

Master Gardener Training - Vegetables

Becky SidemanUNH Cooperative Extension, Sustainable Horticulture Specialist

Part I.

- Site & soil preparation for vegetable gardens- Scheduling and planting- Special issues w/managing vegetables

Part II.

- Common problems

Botanically speaking:

Fruit = the developed ovary of a seed plant with its

contents and accessory parts

Horticulturally speaking:

Fruits of annual plants are considered vegetables.

Vegetable = a herbaceous plant cultivated for food, as the

cabbage, potato, bean, etc; also, the edible part or parts of

such plants, as prepared for market or table. (Webster’s

Dictionary)

2

Leaf: Lettuce, kale, spinach

Immature Fruit: Cucumber, zucchini

Mature Fruit:Tomato, pepper,Melon, pumpkin

Flower: Broccoli, cauliflower

Root: Sweetpotato, carrot

Tuber :Potato

Petiole:Celery

Buds:Brussel sprout, onion

Vegetables can also be defined by edible part:

Vegetable plant families:

Apiaceae – umbelsBrassicaceae – cole crops/ crucifersChenopodiaceae

Cucurbitaceae - cucurbitsSolanaceae – the nightshade familyFabaceae – legumes

Liliaceae/Alliaceae – alliumsPoaceae – grasses/graminae

Plus a few minor ones…

Related crops have similar:

Temperature preferences

Nutritional requirements

Biochemical characteristics

Pests and diseases

3

Apiaceae - carrot, celery, fennel, dill, cilantro

Asteraceae - lettuce, sunflower, artichoke, cardoon

Brassicaceae - cabbage, broccoli, cauliflower

Photo credit: University of Maryland

4

Chenopodiaceae – spinach, beet, lambsquarters

Cucurbitaceae - cucumber, squash, melon

Fabaceae (legumes) - beans, peas, lentils

5

Liliaceae (alliums) – onion, garlic, chive, leek

Poaceae - grasses

Solanaceae - tomato, potato, eggplant, tobacco

6

Perennial exceptions:

Horseradish

(brassicaceae) Rhubarb

(polygonaceae)

Asparagus

(asparagaceae)

Site & Soil Preparation for Vegetable Crops

A good site for vegetables:

• light (>10 hrs)• well-drained• fairly level

Avoid:• low spots• windy areas• trees• buildings

7

Remove perennial weeds before you plant.

• Remove by hand• Mulch to smother• Herbicides

This plot was covered with a piece of black

plastic from around June 15 until Aug 15.

Tillage – incorporates soil organic matter, make soil loose and friable

• 8-10 inches ideal• taproot crops especially sensitive

8

Fall is the ideal time to prepare the ground, for

many reasons… but cover the soil!

Adjust pH with limestone or woodash

Soil test FIRST…

pH affects solubility of elements and nutrient uptake – Most vegetables do best at pH 6.5-7.0-- Potatoes are often grown at lower pH (5.0) to reduce scab

9

Gardening in tight spaces

Crops for container gardening:

- herbs- lettuce/greens- tomato- pepper- cucumber- zucchini

…and many more!Determinate varieties best

Containers

- avoid treated wood- drainage holes a must- at least 6-8” deep

10

Media

- garden soil is too heavy & dense- light peat-based mixes are better- ideally less than 50% compost- countless recipes available

http://attra.ncat.org/attra-pub/potmix.html

• Vegetable Garden Scheduling &

Transplanting

• Established crop requirements

• Technologies & Techniques

Half-Hardy

Artichoke

Beet

Carrot

Cauliflower

Celery

Chard

Chinese cabbage

Endive

Lettuce

Parsnip

Potato

Cool Season Crops Warm Season Crops

Tender

Cowpea

Snap bean

Edamame

Sweet corn

Tomato

Very Tender

Cantaloupe

Cucumber

Eggplant

Lima bean

Okra

Pepper

Pumpkin

Squash

Sweetpotato

Watermelon

Hardy

Asparagus

Chive

Garlic

Onion

Leek

Horseradish

Pea

Rhubarb

Spinach

MOST Brassicas

Adapted from Knott’s Handbook for Vegetable Growers, 4th

Edition

60-65F50-60F45-50F40-45F

11

Cold Frames

Cloches

Low tunnels….

And caterpillartunnels ….

12

Tomato, pepper, eggplant

Squash/pumpkin, melon, cucumber

Broccoli, cauliflower, kale, brussels sprouts

Celery, fennel, herbs

Beets, onions

Sweet corn & popcorn

USUALLY not: beans, peas, potato, garlic

Definitely NOT: carrot, parsnip,

sweetpotato

Vegetables that benefit from transplanting…

Seedlings need adequate nutrition and light.

Stocky, fat, green

13

2-3 weeks: All cucurbits

4-6 weeks: Tomato, lettuce, chard, All

brassicas

6-8 weeks: Eggplant, pepper

Scheduling transplants:

For fertility, 2 choices:

“pot up” or fertilize after the first 2 wks.

A sunny window

may not be enough

light for long-term

growth.

Supplemental

lighting is most

efficiently done with

fluorescent full-

spectrum bulbs.

Supplemental light?

Pick ideal transplanting weather (overcast)

Water in thoroughly

Harden off

Gradual reduction in light, fertility – and gradual

exposure to UV light and wind

Avoid “transplant shock”

14

Seeds should be DRY and COOL.

Optimum storage conditions:

In most cases, 4-5% moisture and 40F.

Storing Vegetable Seeds

If in doubt, TEST germination of seeds.

(and if it’s important to you – buy new)

Light Feeders

Legumes (peas, beans)

Onions

Leeks

Garlic

Carrot

Parsnips

Sweet potato

Heavy Feeders

Asparagus

Beet

Broccoli, Cauliflower

Celery

Corn

Eggplant

Pepper, Potato, Tomato

Pumpkin, Squash,

Melon

Fertilization

15

Fertilizing

Nutrient

uptake

preplant sidedress

More frequent applications = more efficient use

Watering

• Water needs are determined by:

- sun

- temperature

- wind

- plant size

- soil type

- mulches

Irrigating Vegetable Crops

• Early AM, not late afternoon

• Water deeply (5-6 inches) to

encourage good rooting

• Most critical times:- at transplanting- while storage organs are developing

A rough guideline: 1-2” per week

16

Harvesting & Postharvest Care

For most fruiting vegetables:

- harvest as early as possible to ensure continued production

Unless maturity is essential:

- winter squash, pumpkins

- melons

For leafy vegetables:

- harvest early AM- get cool as quickly as possible

17

Some crops benefit from curing:

- winter squash

- pumpkin

- sweetpotato

- onions

Curing = treatment for a short period of time (<2 wks) at high temperature (80-85F) to heal wounds

Cool (32F) Warm (50-60F)

(40-60F)

Low Humidity

(65-75%)

High Humidity

(90%)

Garlic

Onion

Leek

Beet

Carrot

Turnip

Squash

Pumpkin

Sweetpotato

Potato

Four ideal storage conditions:

Root cellar Living space

Crops Sensitive to Chilling Injury• Highly Sensitive

– Basil– Cucumbers– Summer Squash– Sweet Potatoes

• Somewhat Sensitive

– Snap beans– Muskmelon– Peppers– Winter Squash– Tomatoes

18

Mulches = Materials that cover the

ground to prevent the growth of

weeds. - Crucial to block LIGHT (not clear!)

There are TONS of good reasons to use mulches:

- Conserves soil moisture- Conserves nutrients – no leaching!- Some warm the soil, others cool

- Organic mulches decompose and amend soilDrawbacks:

- Expense- Habitat for voles, slugs, etc.

Mulches for Soil Warming

Clear > IRT > Black > Reflective

Mulches for Soil Cooling

White, Straw

Crops that respond well to high soil

temp:- melon, cucumber, watermelon

- pepper, tomato, eggplant- sweetpotato, sweet corn

Crops that respond well to cool soil

temp:- broccoli, lettuce

19

Staking and Trellising

• increases light and airflow

• increases ease of picking

• uses space efficiently

• good for vining or tall varieties of many crops

Basket weave system:

20

Insect

management

in

vegetables