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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 Regional Gardening Tips Oregon is divided into four growing regions. Identifying your region will help you choose vegetable varieties and planting dates suitable to the growing conditions in your area. See the story on planting guidelines for suggested planting dates. Oregon coast: cool, long season of 190 to 250 days. Western valleys: 150- to 250-day season; warm days, cool nights; length of season may vary from year to year. (See section on gardening in the Rogue Valley.) High elevations: short growing season of 90 to 120 days; frost can occur during any month. (See section on gardening in central and eastern Oregon.) Columbia and Snake River valleys: 120 to 200-day season; hot days, warm nights; length of season fairly well defined. The Coast Cool-weather crops such as radishes grow well in coastal Oregon's climate. Gardening on the Oregon coast isn't impossible. On the other hand, it isn't easy. The wind, fog, and cool temperatures are natural obstacles to gardening success. However, if you match your plant needs and garden design to the coastal climate, gardening by the beach can be a rewarding experience. Garden plants need sun, moisture, and nutrients to grow vigorously. Too much or too little of any of these will cause problems. Lack of sunlight and warmth often are limiting factors on the coast. Sometimes, removing trees will make a big difference. Orienting garden rows in a north-south direction helps maximize sunlight to all parts of the garden. Make the most of available heat by planting on the south side of a wall or building. Plastic hotcaps, cloches, row covers, or small greenhouses can modify the planting environment to increase heat. Be sure to provide ventilation when using plastic covering or plants will dry out. Heavy rainfall in the spring is a problem where soils drain slowly. Add organic matter and use raised beds to improve soil drainage and speed up soil warming. (See story on raised beds.) Many coastal soils are sandy and don't hold water well. Gardens on these soils need additional organic matter and frequent watering during the drier summer months. A lack of nutrients limits plant growth in any gardening environment. Be sure to apply adequate fertilizer to coastal gardens during the growing season. (See story on fertilizing.) Wind protection is essential on the coast. Wind causes moisture to evaporate from plant leaves more quickly than roots can take in new moisture. This causes drought stress, which in windy areas can occur even when the ground is saturated with moisture. Place small fences, tires, shade cloth, snow fencing, or other objects around plants to break the wind. A key detail in coastal gardening success is the selection of appropriate varieties. Cole crops, root crops, lettuce, peas, spinach, zucchini, leeks, and onions do well here. Tomatoes and corn will do well if you use short-season varieties and some type of row covering to speed germination and early growth. (See story on growing warm-season crops in cool-season area.) Top The Rogue Valley In the Rogue Valley, cool nights in early summer can delay fruit set on tomatoes, but tomatoes will set on by midsummer, giving them time to ripen during the warm, sunny days of early fall. Gardeners in the Rogue Valley enjoy an excellent climate for gardening and a wide variety of fertile valley soils. Warm, sunny weather in late spring, summer, and early fall provides good growing conditions with a minimum of garden plant diseases. Year-round gardening is possible, with mild winters where temperatures seldom drop below 20°F. Variety of soils Rogue Valley soils range from sandy loam to heavy clay. Most of the clay soils originate from rocks of ancient volcanic activity in the Cascade Mountains. Granite soils are from older, more durable and slowly weathered rocks of the Siskiyou Mountains. The granite rock materials formed sandy loam soils that drain well but are not as rich in nutrients as clay soils. Gardeners usually prefer loam or sandy soils. Clay soils drain and dry slowly. When wet, they are sticky and difficult to garden. "Heavy" clay soils live up to their name when gardeners try working them too early in the spring. If you work clay soil when it's too wet, it will make a poor seedbed of hard clods. Prepare garden soil when it's no longer sticky and when a handful squeezed together doesn't form a hard lump. (See story on tilling.) Improve clay soils by adding organic matter, an excellent soil amendment regardless of soil type. In well-drained granite soils, organic matter improves water retention, while in heavy clay soils it improves soil drainage. (See story on improving soil.) Soils that drain well will warm faster in the spring, but may become too warm for some crops during midsummer. Experienced gardeners rotate from cool- to warm-season crops in early summer to gain the advantage of increased soil temperature. A mild climate The Rogue Valley climate is influenced by the nearby Pacific Ocean, with its marine warmth in winter and cool but dry air in summer. The moderating air mass is carried onshore by prevailing westerly winds. In spite of some warm midsummer days, the growing season's average daily temperature is 70°F. These warm days are offset by cool nights, as cold air drains down from the surrounding mountain slopes. During early summer, these cool nights may prevent fruit set for crops such as tomatoes. Sufficiently warm nights eventually will prevail, however, and tomato fruit will be set by midsummer. It's possible to grow winter garden crops successfully in the Rogue Valley during most years, and such crops can be grown in the valley consistently if they are given some protection, particularly on days of extreme low temperatures. (See story on fall and winter gardening.) Although annual extreme lows range between 10 and 20°F, the average daily low dips only slightly below freezing during December and January. The frost-free period is 165 to 170 days, beginning about the first of May and ending in mid- to late October. This varies slightly from one location to another in the valley. These dates are critical for growing tomatoes, corn, potatoes, squash, cucumbers, and other warm-season crops susceptible to frost injury. Try to select vegetable varieties that will mature within the frost-free period. Since 75 percent of the average annual rainfall comes between November and March, take advantage of breaks in the weather to prepare your garden for a mid-February planting of peas and onions. Avoid early planting in areas that remain soggy after a rain. Plant corn and potatoes around mid-April even though near- or below-freezing temperatures still might occur. The first plants may be nipped back, but damage will be minimal and plants will continue to grow and emerge from the ground as the weather warms. Other warm-season crops do best with mid-May to early June plantings, when there is less chance of frost and warmer soil conditions prevail. Rogue Valley fall weather is ideal for cool-season crops. Try a midsummer planting for fall harvest. Midsummer planting of cool-season spring crops also is recommended where soggy soils prevent early gardening. Choice of garden site Due to variations in the topography of the valley floor, foothills, and mountainous areas, and in tree density on forested sites, the Rogue Valley offers varied microclimates of sunlight exposure, temperature, humidity, and air drainage. Select your garden site with care and take advantage of the climatic variation within your yard. It may determine your success as a gardener. For example, the south side of a house or slope is a warmer site than the north side. A southern exposure receives maximum sunlight throughout the gardening season. Plant crops that like more warmth in an area with southern exposure. Plant shade-tolerant leafy vegetables on the north side of a building or on a north slope. Locate your garden where it will receive at least 6 hours of sunlight each day (8 to 10 hours is preferred). Avoid planting vegetables near buildings or trees that shade your garden. In addition, the roots of nearby trees and shrubs will rob vegetables of nutrients and water. (See story on site selection.) Avoid frost pockets or areas that warm slowly in the spring. Frost will build up in areas lacking air drainage, such as low spots at the base of a hill or at the foot of a slope bordered by a solid fence. Wherever you locate your garden, be sure a readily available supply of water is nearby. Garden soil on hot and windy sites in the Rogue Valley can lose up to a 12 inch of water per day. Since there is very little rainfall during the summer, watering is necessary at planting time and throughout the summer. (See story on watering.) If watering your garden is difficult and time-consuming, it will become more work than you want to do during the hot days of July and August. Top Central and Eastern Oregon Root crops such as potatoes, carrots, and beets do well in areas with short growing seasons and cool nights such as central and eastern Oregon. Although it may not be a gardening paradise, central and eastern Oregon is more than a wide expanse of high desert. Successful vegetable and fruit gardening is possible east of the Cascades if you take into account the area's special and widely varying climate and soil characteristics. The growing season may be as short as 80 to 90 days in central Oregon at elevations above 3,500 feet. In some of the lower elevations and river valleys, growing seasons may exceed 130 days. Also, large fluctuations in daytime and nighttime temperatures, often as much as 40-45°F, affect vegetable and fruit production. Cool nights reduce the chances of successfully growing vegetables that like warm nights, such as lima beans and eggplants. (See story on growing warm-season crops in cool-season area.) Soil types Soil types in central and eastern Oregon vary widely. Light-textured soils, low in organic matter, nutrient content, and water-holding capacity, are found in parts of central Oregon and the eastern Columbia Basin area. These soils may require frequent applications of fertilizer and water. At the other extreme are the heavy soils high in soluble salts (which can create an alkalinity problem) found in many eastern Oregon areas. Added organic matter such as manure or compost generally is beneficial for most central and eastern Oregon soils. (See story on improving soil.) Specific information for each area is available from county offices of the OSU Extension Service or from local garden centers. Choosing crops Concentrate on those vegetables adapted to your particular area. Avoid planting vegetables that require special, intense, or improved growing conditions. Root crops (e.g., potatoes, carrots, and beets) and cold-tolerant crops (e.g., cabbage, chard, leaf lettuce, and kohlrabi) do well in high-elevation gardens. Short-season vegetable varieties offer the best chance of success. For example, cool nights during the growing season may cause a 65-day tomato to require 75 to 80 days or more to mature. Planting dates Planting dates for high-elevation, short-season areas generally lag behind those in other parts of the state. In high areas, gardens usually are planted from mid-May, for cold-tolerant plants, to mid-June. Later plantings often fail to mature before fall frosts. See the story on planting guidelines for suggested planting dates. Use plant protection devices, such as row covers, hotcaps, and Walls-o-Water, to extend the growing season for vegetables requiring longer periods to mature. Top The Columbia River Valley In areas along the Columbia River, where the growing season approaches or exceeds 120 days, planting dates can be moved up to early May. For gardens in lower elevation areas along the Columbia River, frost and cold are not the main enemy. In the river gorge, beginning in mid-spring and extending through summer, heat and steady winds create problems for gardeners trying to establish fruit and vegetable plantings. Starting a garden in a steady 20-mile-per-hour breeze with temperatures approaching the mid-80s can be a challenge. Frequent, light watering is the only way to keep seedlings from drying out. Place a rock or secure a roofing shingle on the windward side of seedlings to break the wind and help plants become established. As the season progresses and temperatures rise above 100°F, protection from heat becomes critical. Plants can wilt and die quickly if not properly cared for. Give established plants plenty of water. Watering 60 to 90 minutes at a time, three times a week, will keep plants growing vigorously. For season-long protection from the wind, plant a hedge that will grow 4 to 5 feet high on the west side of the garden. It will provide some wind protection yet allow plenty of light to reach garden plants. 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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.