When to Plant and Harvest Grains, Nuts & Legumes in Washington

Washington State’s diverse climate zones—from the rain-soaked coastal areas to the dry, sunny inland regions—offer unique opportunities for growing a variety of grains, nuts, and legumes. Understanding the optimal planting and harvesting times for these crops is essential for maximizing yield and quality. This article provides a comprehensive guide on when to plant and harvest common grains, nuts, and legumes suited to Washington’s environment.

Understanding Washington’s Growing Conditions

Washington is characterized by two primary agricultural regions:

• Western Washington: Known for its temperate, maritime climate with mild, wet winters and cool summers.
• Eastern Washington: Features a dry continental climate with hot summers and cold winters, benefiting from irrigation.

The timing of planting and harvesting depends heavily on these regional climate differences, as well as on soil type, elevation, and microclimates. Additionally, the length of the frost-free season (growing season) varies greatly between regions—from about 120 days in colder areas to over 180 days in milder zones.

Grains in Washington

Wheat

Wheat is one of Washington’s largest crops. Both winter wheat and spring wheat are grown in the state.

• Winter wheat is primarily grown in Eastern Washington.
• Spring wheat tends to be planted where winters are too harsh or where the growing season is shorter.

Planting Time

• Winter Wheat: Plant from mid-September to mid-October. This allows seeds to establish before winter dormancy.
• Spring Wheat: Plant from late March through April after soil temperatures reach around 40°F (4°C).

Harvest Time

• Winter wheat typically matures by late July to early August.
• Spring wheat is harvested in late August through September.

Barley

Barley is another important grain crop in Washington, used both for feed and malting.

Planting Time

• Barley can be planted either as a winter or spring crop.
• Winter barley is planted early September to October.
• Spring barley is planted from late March to early April.

Harvest Time

• Winter barley is harvested from mid-July to mid-August.
• Spring barley matures later, from late August to early September.

Oats

Oats are less common but still grown in parts of Eastern Washington.

Planting Time

• Best planted in early spring (March or early April) as soon as the soil can be worked.

Harvest Time

• Harvest usually occurs by late July or early August.

Corn (Grain Corn)

Grain corn production is more limited but increasing due to demand for livestock feed.

Planting Time

• Plant after the soil warms up—usually mid-April through May in Eastern Washington.

Harvest Time

• Usually harvested in September or October when kernels reach full maturity.

Nuts Suitable for Washington

Washington’s nut production mainly focuses on tree nuts like hazelnuts (filberts), walnuts, and chestnuts. These require patience as they take several years to mature but provide valuable yields over time.

Hazelnuts (Filberts)

Hazelnuts are well adapted especially to Western Washington’s milder climate.

Planting Time

• Best planted during dormancy in late fall (November to early December) or early spring before bud break (February to March).

Harvest Time

• Typically harvested from late August through early October when nuts begin dropping naturally.

Walnuts

Walnuts require a longer growing season and are generally more successful in warmer parts of Eastern Washington.

Planting Time

• Dormant trees are best planted in late winter or early spring (February through March).

Harvest Time

• Walnuts usually mature between September and October when hulls start splitting open.

Chestnuts

Chestnuts thrive best where there is good drainage and moderate rainfall—suitable for some parts of Western Washington.

Planting Time

• Typically planted while dormant, between late fall and early spring.

Harvest Time

• Chestnuts ripen in mid-fall, mostly during October and November.

Legumes in Washington

Legumes such as peas, lentils, chickpeas, dry beans, and fava beans have gained popularity because of their nitrogen-fixing abilities that improve soil health alongside providing nutritious food sources.

Peas

Field peas are grown extensively across Eastern Washington as a rotation crop with cereals.

Planting Time

• Planted early—usually from mid-March through April—to avoid hot weather during flowering.

Harvest Time

• Harvested when pods dry out by mid-July to early August depending on variety.

Lentils

Lentils are well-suited for dryland farming areas of Eastern Washington due to their drought tolerance.

Planting Time

• Seeded in early spring (March-April), similar to peas.

Harvest Time

• Ready by mid-August to September when pods turn brown and seeds harden.

Chickpeas (Garbanzo Beans)

Chickpeas require warmer soils but do well under irrigation in Eastern Washington.

Planting Time

• Plant after frost risk passes—usually late April through May.

Harvest Time

• Typically harvested from late August through September when pods dry thoroughly.

Dry Beans

Varieties like kidney beans, pinto beans, and black beans are grown mostly under irrigation systems.

Planting Time

• Usually planted from late April through May once soil has warmed above 60°F (15°C).

Harvest Time

• Beans mature between late August and October depending on the variety.

Fava Beans (Broad Beans)

Fava beans prefer cooler weather and can be grown as a winter crop with proper protection or planted very early spring.

Planting Time

• In Western Washington, fall planting (October-November) is possible.
• In Eastern Washington, plant very early spring (March).

Harvest Time

• Pods mature around June-July if planted in fall or summer if planted in spring.

Key Considerations for Successful Crop Timing

1. Soil Temperature & Moisture: Seed germination depends heavily on soil temperature. Testing soil temperature before planting ensures seeds won’t rot or fail to sprout.
2. Frost Dates: Knowing your local average last frost date helps prevent cold damage to young plants.
3. Irrigation Availability: Many Eastern Washington crops rely on irrigation; planning planting dates around water availability improves success.
4. Crop Rotation: Incorporating legumes into rotation helps reduce disease pressure and increases soil fertility.
5. Varietal Selection: Choose varieties adapted specifically for Washington’s climates and your specific zone for best results.
6. Pest & Disease Management: Timing planting so that vulnerable growth stages avoid peak pest seasons can reduce losses without heavy chemical use.

Conclusion

Planting and harvesting times for grains, nuts, and legumes vary widely across Washington due to its diverse climates. By aligning crop cycles with local conditions—taking into account temperature thresholds, moisture levels, frost risk, and seasonal daylight patterns—growers can maximize productivity. Whether you’re cultivating wheat on a large scale in the Columbia Basin or nurturing a backyard hazelnut orchard near Seattle, understanding these timing guidelines will help you achieve healthy crops and bountiful harvests every year. Investing time into careful planning pays off handsomely at harvest time!