In the Pacific Northwest, we basically have three main growing seasons: two cool, wetter seasons (spring and fall) and the warmer months of summer in between. Early spring crops must be able to withstand cold soil conditions and low nighttime temperatures. Salad greens, garden peas, root crops, and brassicas are the majority of the crops most suitable to cool season growing.
Warm-season crops must be planted when soil temperatures have risen above at least 50 to 60 degrees (Fahrenheit) and nighttime temperatures are staying at 50 degrees or warmer. In the Willamette Valley, these conditions usually arrive in early or mid-May. Raised beds and large containers can warm up faster than in-ground soil, and so can different areas in your garden. Use a soil thermometer to check for ideal planting times and conditions.
Since we talk a lot about growing tomatoes at home, it’s time to pay some attention to the many other summer vegetables we can grow just as well!
Grow fresh green beans or shelling beans for drying. Growth habit may be vining (pole, runner beans) or bush style. Vining plants should be grown up a trellis or teepee, while bush beans can be planted in a row with no support and will grow to about knee-high. Plants are shallow rooted and need regular watering and mulching. They are best when direct-seeded into garden soil. Beans are ready for harvest about two weeks after bloom; harvest every 3–5 days when ripe to keep productive.
Carrots grow best in deeply worked, loose soil with a pH of 6.0–7.0. Directly sowing seeds is preferred to transplanting, if possible. Avoid split roots by watering regularly, and avoiding overfertilizing to prevent forked or misshapen carrots. Cover crowns with extra soil as they grow to discourage green shoulders. Water plants prior to harvesting for highest moisture content and cut tops off before storing to keep them fresh. Try round carrots like Parmex, Kuroda, or Nantes types for harder, heavier soils. Carrots can also be grown as a fall or winter crop.
Corn may be transplanted from starts, but is better when direct seeded and does best in fertile, well-drained soil with a pH of 6.0–7.0. It is critical to wait for soil to reach optimum temperature (70 degrees for best germination) and important to provide plenty of nitrogen during the early growing stage since corn is a heavy feeder. Be sure to water evenly and deeply. For proper wind pollination, plant individual corn varieties in blocks of at least four rows.
Cucumbers are another vegetable available as transplants, but grow best when direct seeded into the garden using well-drained soil with a pH of 5.5–7.0. Keep soil evenly moist, but not wet for germination, and be sure to provide consistent, even watering during early growth and fruit development. Trellis-growing, mulch, or raised beds can improve yields and keep fruit straight and pest free. Harvest regularly for best productivity.
Eggplants do best with lots of heat and require a long growing season, so using transplants is usually best. Provide them with fertile, well-drained soil and mulch and/or use row covers for extra warmth in spring. Optimum growing conditions are when daytime temperatues are 80–90 degrees. Harvest when skin is smooth and shiny.
Melons prefer rich, well-drained soil and need warm soil to germinate. They may be planted from seed once soil is at least 65 degrees or can be transplanted from starts. Watermelon is not as cold-tolerant as other melons and should be mulched and/or covered for early spring warmth. Smaller fruiting varieties have a better chance of ripening; try Sugar Baby Watermelon or Charentais Cantaloupe.
Peppers grow best in fertile, well-drained soil with a pH between 5.5 and 6.8. Plant with extra calcium (bone meal, lime) for better productivity. Plants grow best in raised beds or containers and grow slowly in cool soil, so transplants are usually better than direct seeding into the garden. Fruit set occurs between temperatures of 65 and 85 degrees; pinch some flowers to allow ripening fruit to grow larger. Green peppers slowly ripen to yellow, orange, and red. Sweet bell peppers, mild sauté peppers, and spicy hot peppers all can be grown the same. Pepper heat increases when plants are slightly drought stressed.
Squash prefers well-drained, fertile soil with soil temperatures at least 65 degrees or warmer. It may be direct sown or planted from transplants. Be sure to plant bush varieties 3–4 feet apart and vining varieties 4–6 feet apart. Squash are monoecious (male and female flowers grow separately on the same plant) and need insect pollination to set fruit; plant bee attracting flowers such as Borage or Sweet Alyssum nearby for better pollinator traffic. Harvest summer squash every 3–4 days to keep productive and avoid over-sized fruit; harvest winter squash (Acorn, Delicata, Butternut) when fully mature and firm; wash and cure for storing.
Other Summer Crops
In addition to these basic summer edibles, there are many other crops that can be grown this time of year. Other than carrots, root crops like beets, radish, parsnip, turnip, and rutabagas can be direct-sown in spring or late summer, but tend to grow better in cool conditions and when kept evenly watered. Broccoli, cauliflower, Brussels sprouts, and cabbage can also be grown during the summer, but may have a tendency to flower or go to seed during extreme temperatures and can struggle with more pests during summer months than when grown as a fall or winter crop. Salad greens such as lettuce, kale, and chard need to be watered evenly and consistently to avoid bitter flavors; look for heat-tolerant or “slow-bolt” varieties for summer growing.
As summer crops are harvested and slow in productivity, fall and winter crops may be planted in their place. Cool-season varieties may be planted again as early as July for harvest in late fall, winter, or even the following spring.