Garden Planting Calendar
OK Garden Planting Guide
Oklahoma Cooperative Extension Service
Garden Planning Guide
David Hillock Extension Consumer Horticulturist
Extension Consumer Horticulturist
Oklahoma Cooperative Extension Fact Sheets
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Well-planned, properly managed home gardens can furnish Oklahoma families with flavorful, high quality, fresh vegetables from spring through fall, as well as for processing or storing for winter.
The amount of money invested in seeds, fertilizer, pesticides, and a few tools is more than offset by the enjoyment, healthful outdoor exercise, and fresh "homegrown" flavor.
Choosing the Site
The selection and preparation of the garden site is an important key to growing a home garden successfully. An area exposed to full or near full sunlight with deep, well-drained, fertile soil is ideal. The site should also be located near a water supply and, if possible, away from trees and shrubs that would compete with the garden for light, water, and nutrients.
While these conditions are ideal, many urban gardeners have a small area with a less than optimal site on which to grow vegetables. Yet, it is still possible to grow a vegetable garden by modifying certain cultural practices and types of crops grown. Areas with light or thin shade can be used, such as those under young trees, under mature trees with high lacy canopies, or in bright, airy places which receive only one to two hours of direct sun per day. There are several vegetables which will grow under these conditions, including beans, beets, broccoli, cabbage, cauliflower, chard, kohlrabi, leaf lettuce, peas, potatoes, radishes, rhubarb, spinach, and turnips. Unfortunately, few vegetables will grow well under full, dense shade. If the site is not well drained or if the soil is thin, the use of raised beds can help with this problem.
Planning the Garden
The accompanying chart should be of help in determining family requirements of the different vegetables.
Perennial vegetables (asparagus, rhubarb, winter onions, etc.) should be planted at one side or end of the garden for efficient operation. The hardy vegetables planted early in the season should be planted together, so they may be followed with late season plantings of the same or other vegetables. Vegetables requiring similar cultural practices should be grouped together for ease of care.
The chart groups vegetables as cool season or warm season crops, indicating under which conditions they grow best. Crops classed as cool season may be planted earlier in the season and thrive best under cool conditions (average daily temperatures of 70oF or less), while those grouped as warm season crops grow better during warm temperatures (average daily temperatures ranging between 70 to 90oF).
Based on the temperature that the plants will withstand, vegetables are hardy, semi-hardy, tender, or very tender. Hardy types may be planted before the last killing frost. The semi-hardy ones will be injured by a hard frost, but will grow in cool weather and not be harmed by a light frost. Tender plants are injured or may be killed by a light frost but can withstand cool weather, while the very tender are injured by cool weather.
Differences in suggested planting dates range from the earliest for southeast Oklahoma to the latest for the northwest part of the state.
In order to have a successful garden, the gardener must follow a few rules. The following tips may help to prevent some common garden problems from occurring, or help overcome those that do arise:
• Sample soil and have it tested every three to four years.
• Apply fertilizers in the recommended manner and amount.
• Make use of organic materials such as compost where available.
• Use recommended varieties.
• Thin plants when small.
• Use mulches to conserve moisture, control weeds, and reduce fruit rots.
• Avoid excessive walking and working in the garden when foliage and soil are wet.
• Examine the garden often to keep ahead of potential problems.
• Keep the garden free of weeds, insects, and diseases.
• Wash and clean tools and sprayers after use.
• Rotate specific crop family locations each year to avoid insect and disease buildup.
• When possible, harvest vegetables during the cool hours of the day.
Division of Agricultural Sciences and Natural Resources • Oklahoma State University
Avoid the Following Mistakes:
• Planting too closely, which prevents walking or working in the garden.
• Placing fertilizer directly in contact with plant roots or seeds.
• Cultivating deeply, resulting in injury to plant roots.
• Depending on varieties not recommended for your area; however, do try new releases.
• Watering frequently or excessively so that the soil is always wet and soggy.
• Allowing weeds to grow large before elimination.
• Applying chemicals or pesticides in a haphazard manner, without reading label directions or proper mixing.
• Using chemicals not specifically recommended for garden crops.
• Storing leftover diluted spray.
Garden Planning Guide
Spacing Spacing Quantity
Time Feet of Row Days to Method Between Within Depth to Needed Frost
Vegetable to Plant Per Person Harvest of Planting Rows Rows Cover Seed Per Person Tolerance
- Asparagus Fall or Spring 10-20 — Crowns 4 ft. 2 ft. 6 in. 3-5 Hardy
- Beet March 10-20 50-70 Seed 1 1/2 ft. 4 in. 1 in. 1/8 oz. Semi-Hardy
- Broccoli March 10 80-90 Plants 3 ft. 1 1/2 ft. 6-7 plants Hardy
- Cabbage Feb. 15 to March 10 10-20 60-90 Plants 3 ft. 1-1 1/2 ft. 6-15 plants Hardy
- Carrot Feb. 15 to March 10 20 70-90 Seed 1 1/2 ft. 3 in. 1/2 in. 1/8 oz. Semi-Hardy
- Cauliflower Feb. 15 to March 10 15 70-90 Plants 3 ft. 1 1/2 ft. 6-8 plants Semi-Hardy
- Chard, Swiss Feb. 15 to March 10 10 40-60 Seed 1 1/2 ft 3 in. 1/2 in. 1/2 oz. Semi-Tender
- Kohlrabi Feb. 15 to March 10 10 50-70 Seed 2 ft. 6 in. 1/2 in. 1/8 oz. Hardy
- Lettuce, Head Feb. 15 to March 10 20 60-90 Seed or Plant 1-1 1/2 ft. 1 ft. 1/4 in. 1/8 oz. or Semi Hardy
- Lettuce, Leaf Feb. 15 to March 10 20 40-70 Seed or Plant 1-1/ 2 ft. 3 in. 1/4 in. 1/8 oz or Semi-Hardy
- Onion Feb. 15 to March 10 25 60-120 Sets 1-1 1/2 ft. 4 in. 1 in. 1/4 qt. sets Hardy
- Onion Feb. 15 to March 10 25 60-120 Plants 1-1 1/2 ft. 4 in. 1 in 1/8 oz. or Hardy
- Peas, Green Feb. 15 to March 10 30 60-90 Seed 3 ft. 2 in. 2 in. 1/4 lb. Hardy
- Potato, Irish Feb. 15 to March 10 50 90-120 Tuber pieces 3 ft. 1 ft. 4 in. 6-8 lbs. Semi-Hardy
- Radish March 1 to April 15 15 25-40 Seed 1 ft. 2 in. 1/2 in. 1/8 oz. Hardy
- Rhubarb Fall or Spring 12 — Crowns 4 ft. 2 ft. 3 in. 3-4 crowns Hardy
- Spinach Feb. 15 to March 10 35 50-70 Seed 1 1/2 ft. 2 in. 1/2 in. 1/4 oz. Hardy
- Turnip Feb. 15 to March 10 20 50-60 Seed 1 1/2 ft. 3 in. 1/2 in. 1/8 oz. Hardy
These dates indicate planting times from southeast to northwest Oklahoma. Specific climate and weather may influence planting dates. For cool season vegetables, the soil temperature at the depth where the seeds are planted should be at least 40°F.
6004-2 6004-3 Other OSU Extension Gardening Publications BAE-1511— Trickle Irrigation for Lawns, Gardens, and Small Orchards HLA-6005— Mulching Vegetable Garden Soils HLA-6007— Improving Garden Soil Fertility HLA-6009— Fall Gardening HLA-6012— Growing Tomatoes in the Home Garden HLA-6013— Summer Care of the Home Vegetable Garden HLA-6032— Vegetable Varieties for Oklahoma HLA-7313— Home Garden Insect Control HLA-7625— Common Diseases of Tomatoes, Part I: Diseases Caused by Fungi. EPP-7626— Common Diseases of Tomatoes, Part II: Diseases Caused by Bacteria, Viruses, and Nematodes EPP-7627— Common Diseases of Tomatoes, Part III: Dis-eases Not Caused by Pathogens EPP-7635— Diseases of Cucurbits (Watermelons, Cucum-bers, Cantaloupes, Squash, and Pumpkins) EPP-7640— Solar Heating (Solarization) of Soil in Garden Plots for Control of Soil-Borne Plant Diseases EPP-7646— Diseases of Asparagus in Oklahoma
Green or Wax April 10-30 40 50-60 Seed 1 1/2 ft. 4 in. 1 in. 1/8 lb. Tender Beans,
Pole April 10-30 20 60-90 Seed 3 ft. 8-12in. 1 in. 1/8 lb.
- Bean, Lima April 15-30 20 90-120 Seed 2-3 ft. 6 in. 1 in. 1/8 lb.
- Tender Cantaloupe May 1-20 20 80-100 Seed or Plants 3-5 ft. 2-3 ft. 1/2 in. 1/8 oz.
- Very Tender Cucumber April 10-30 or later 5-10 50-70 Seed or Plants 3-5 ft. 2-3 ft. 1/2 in. 1/8 oz. Very Tender Eggplant April 10-30 5-10 80-90 Plants 3 ft. 1 1/2 ft. 3-5 plants
- Very Tender Okra April 10-30 or later 20 60-70 Seed 2-3 ft. 1 1/2 ft. 1 in. 1/4 oz.
- Tender Pepper April 10-30 or later 10 90-110 Plants 3 ft. 2 ft. 5 plants
- Tender Pumpkin April 10-30 or later 30 90-120 Seed 5 ft. 3-4 ft. 1 in. 1/8 oz.
- Tender Southern Pea May 1- June 10 20 85-100 Seed 3 ft. 4 in. 1 in. 1/8 lb.
- Tender Squash, Summer April 10-30 or later 10-20 40-60 Seed or Plants 4 ft. 3 ft. 1 in. 1/8 oz. Very Tender Squash, Winter May 15-June 15 30 110-125 Seed or Plants 5 ft. 4 ft. 1 in. 1/8 oz. Very Tender Sweet Corn Mar. 25-April 30 50 80-100 Seed 3 ft. 1-1/2 ft. 1 in. 1/8 lb.
- Tender Sweet Potato May 1- June 10 25 100-120 Plants 3 ft. 1 ft. 25 plants
- Very Tender Tomato April 10-30 10-20 70-90 Plants 4ft. 2-3 ft. 4-5 plants
- Tender Watermelon May 1-20 10-20 90-120 Seed 5-8 ft. 5-8 ft. 1 in. 1/8 oz.
- Very Tender **These dates indicate planting times from southeast to northwest Oklahoma. Specific climate and weather may influence planting dates. For warm season vegetables, the soil temperature at the depth where the seeds are planted should be at least 50°F.
Common Garden Problems
Symptoms Possible Causes Corrective Measures
Plants stunted in growth; Lack of soil fertility or soil pH Use fertilizer and correct pH according to soil test.
yellow colored foliage. abnormal Use 2 to 3 pounds of complete fertilizer per
100 square feet in absence of soil test.
Plants growing in compacted, Modify soil with organic matter,
poorly drained soil coarse sand. Provide surface drainage.
Insect or disease damage; Use recommended control treatments.
Root Knot Nematode
Iron deficiency Apply iron to soil or foliage. Correct soil pH.
Plants stunted in growth; Low temperature Plant at proper time. Do not use light-colored
purplish colored leaf veins. mulch too early in the season.
Inadequate phosphorus Apply phosphorus at soil test recommendation.
Holes in leaves; leaves Damage by insects Use recommended insecticide treatment.
yellowish and drooping,
or distorted in shape.
Plant leaves with spots; Plant disease Use resistant varieties, remove diseased plants
dead, dried areas; or when noticed and use recommended control
powdery or rusty areas. treatments.
Plants wilt even though Soluble salts too high Have soil tested.
sufficient water is present.
Poor drainage and aeration Add organic matter or sand; ridge soil for
surface drainage. Plant in raised beds.
Insect, disease, or nematode Use recommended varieties and recommended
damage on roots treatments of insecticides and fungicides,
and soil insecticides or nematicides.
Plants tall, spindly, Excessive shade Relocate to sunny area. Keep down weeds.
Excessive nitrogen Reduce applications of nitrogen.
Blossom drop (tomatoes). Hot winds, dry soil Use mulch and water.
Plant heat tolerant varieties.
Low night temperatures Avoid early planting.
Overwatering or disease Reduce watering, use recommended disease
Tomato leaf roll. Excess nitrogen and water Withhold nitrogen, reduce watering.
Curly top disease of beets Remove plant if diseased.
Downward cupping and 2,4-D damage Don’t spray on windy days or when
curling of tomato leaves. temperature is above 80°F.
Leathery, dry, brown blemish Blossom end rot Maintain uniform soil moisture and apply mulch.
on the blossom end of tomatoes, Avoid overwatering and excessive nitrogen.
peppers, and watermelons. Select tolerant varieties.
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Issued in furtherance of Cooperative Extension work, acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, Robert E. Whitson, Director of Cooperative Extension Service, Oklahoma State University, Stillwater, Oklahoma. This publication is printed and issued by Oklahoma State University as authorized by the Vice President, Dean, and Director of the Division of Agricultural Sciences and Natural Resources and has been prepared and distributed at a cost of 20 cents per copy. 1002