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Growing Your Own Growing Your Own Vegetables | Composting | Container Gardens | Fall/Winter Gardens | Fertilizing | Insect Pests | Plant Diseases | Planting Guidelines | Raised Beds | Regional Tips | Site Selection | Slugs | Soil Improvement | Tilling | Warm-season Crops | Watering | Weeds Growing Warm-season Crops in Cool-season Areas  Site selection  Soil preparation  Selecting the right varieties  Planting at the right time  Garden fertility  Modifying the growing environment Oregon's climate affords home gardeners the joy of growing many types of plants. However, in many areas there are limitations when it comes to growing warm-season vegetables (e.g., melons, tomatoes, eggplants, and corn). Even if the growing season is long, air and soil temperatures may be too low for maximum plant growth. Luckily, there are ways to enhance your chances of harvesting large, luscious melons; vine-ripened, juicy tomatoes; and beautiful, purple eggplants. Site selection Choose a garden location that receives full sun and is protected from wind. A site with a slight south- or southeast-facing slope will warm early in the spring and allow colder air to drain to a lower location. Enlarge photo Covering soil with plastic or fabric can increase the soil temperature. Soil preparation A light, well-drained soil (either sandy in texture or amended with organic matter) will warm faster in the spring and stay warmer in the fall. Also, soil in raised beds warms faster and allows for earlier planting. (See story on raised beds.) To further speed soil warming, cover the soil with clear polyethylene plastic film. This can increase the soil temperature by 10-15°F over a period of a few days, thus allowing you to plant earlier in the spring. Selecting the right varieties Select the vegetable varieties best suited to your growing environment. If you don't, all of your other work will be for naught. For tips on what varieties to plant, talk to long-time local gardeners and nursery or garden center personnel, or read seed catalogs. Top Planting at the right time Warm-season vegetables require warm temperatures to germinate (50°F) and warmer day and night temperatures to reach maturity. For germination and early growth, soil temperature is as important as air temperature. See the table of planting dates for guidance on when to start seeds indoors and when to plant seeds and seedlings in the garden. Don't rush! Vegetables planted too early may fail to establish well and may take longer to begin producing and have smaller total yields than those planted after soil and air temperatures have warmed. Garden fertility Proper fertilization is critical when growing long-season vegetables under less-than-optimum temperatures. Plants need to get off to a quick start and have adequate nutrition in order to mature quickly. Phosphorus is especially important for early growth in cool soil. (See story on fertilizing.) Soluble chemical fertilizers are a good choice for plants growing in cold soil since the nutrients are immediately available to plants. Apply organic fertilizers later in the growing season when soil temperatures have risen; the microbes that break down these fertilizers and make them available to plants are most active in warm soils. Top Modifying the growing environment It takes only a small increase in temperature to speed up plant growth and development. Covering plants with cold frames, cloches (clear plastic and hoops), plastic-wrapped tomato cages, or floating row covers (spun polyester) will significantly modify the growing environment (temperature, wind, and humidity). These covers increase air and soil temperatures and conserve heat that otherwise would be lost during the night. Some of these methods can be used with several plants, while others cover only an individual plant. Some are most suitable for modifying the environment at the beginning or end of the season, while others are suitable for use during the entire growing season.

Produced and distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914. Extension work is a cooperative program of Oregon State University, the U.S. Department of Agriculture, and Oregon counties. Oregon State University Extension Service offers educational programs, activities, and materials without discrimination based on age, color, disability, gender identity or expression, marital status, national origin, race, religion, sex, sexual orientation, or veteran's status. Oregon State University Extension Service is an Equal Opportunity Employer. Copyright © 1995- Oregon State University. Disclaimer.