Washington · zones 6b–9a
When to plant garlic in Washington.
Washington's window for garlic runs on the fall side of the season. A second, fall sowing fits Oct 18 to Nov 2. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Garlic dates for a typical Washington season.
Fall round
Oct 18 to Nov 2
Counted back from the ~Oct 18 first frost.
Harvest
~240 days later
~0.2 lb per plant over ~1 weeks.
Washington spans more than one climate: Zone 8 is the most common zone, but the state runs 6b to 9a. That's why the planner works from your ZIP code's frost dates, not your zone: mountain and coastal gardens in the same state can be three weeks apart.
Washington growing notes
Garlic does its best work on Washington's dry side.
Why the east side has the edge
Garlic wants a real winter chill to divide into a proper bulb and a dry finish to cure well, and Washington's arid east side, the irrigated country around the Columbia Basin and the Walla Walla Valley, delivers both better than the wet west side does. Cold nights east of the Cascades supply the 6 to 8 weeks below 40 degrees hardneck garlic needs to split, and the region's low summer humidity means a bulb can finish and dry down without the mold pressure a wetter climate creates. That same dry summer air is why so much of the country's commercial garlic seed stock traces back to arid growing regions in the first place; the crop simply performs better where the finish stays dry.
West-side gardeners can absolutely grow good garlic, but should lean toward softneck types, which need less accumulated cold to bulb properly and tolerate a wetter finish far better than hardneck does, and should plan on curing indoors rather than counting on outdoor air the way an east-side grower can. Music and German Extra Hardy both perform on either side of the mountains for gardeners set on a hardneck anyway, but the east side will generally hand you a bigger bulb from the same clove.
Fall planting into whichever soil you have
Plant cloves 4 to 6 weeks ahead of the ground freezing hard, pointy end up, 2 inches deep and 6 inches apart, regardless of which side of the state you garden on, so cloves get the 2 to 3 weeks of unfrozen soil they need to root before real dormancy sets in; the timing rule does not change even though the soil underneath does. East-side plantings go into the Columbia Basin's naturally loose, sandy volcanic soils, while west-side gardeners are more often working clay that benefits from 2 inches of compost worked in first so the bulb has room to size up without fighting compacted ground.
Mulch matters more on the coast: a loose straw layer over the row through winter buffers west-side beds against the freeze-thaw cycles that heave shallow-planted cloves out of wet ground, a problem the drier east side rarely has to manage.
Scapes, leaf count, and a dry-side curing advantage
Snap scapes, the curling flower stalks hardneck varieties send up in early summer, off as soon as they make their first full curl; removing them redirects real energy into the bulb rather than the flower head. Harvest by leaf count rather than the calendar: dig once 3 or 4 leaves are still green, since each green leaf still on the plant is one intact wrapper layer protecting the bulb.
Curing is where the state's dry side pulls ahead again. East of the mountains, 2 to 3 weeks in a shaded, airy spot is usually enough to dry bulbs fully; west of the mountains, especially in a wet fall, that same cure often needs a fan running indoors to finish the job, because ambient Puget Sound air in October rarely gets dry enough on its own.
In Washington: watch for
The pests that find garlic here.
A middle-length season, about 187 frost-free days, means garlic overlaps onion thrips for a stretch each summer. Check plants every week or two and treat early.
Silvery streaks and curled leaf tips in hot spells.
Organic fix: Insecticidal soap or neem; hang sticky traps.
Seedlings wilt; white maggots in the bulb base.
Organic fix: Float a row cover over the row; rotate beds each year.
Pale patches with fuzzy gray growth in damp weather.
Organic fix: Space for airflow, water early in the day, spray neem.
White rot
Yellowing and dieback, then wilt; fluffy white mold at the bulb base and roots so rotted the plant lifts straight out.
Organic fix: No cure once it is in the soil. Plant clean stock, never follow onions with onions, and keep infested soil off tools and boots.
Your season math: Washington gives garlic about 187 frost-free days, and it needs roughly 240 days to a first harvest. It's a one-planting crop, so time that single sowing well.
Planting garlic in Washington: questions
When should I plant garlic in Washington?+
Washington's window for garlic is in fall: Oct 18 to Nov 2, keyed to the first fall frost around Oct 18.
What USDA zone is Washington?+
Washington spans zones 6b–9a, mostly zone 8. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.
How many garlic plants do I need?+
Depends who you're feeding. The crop page has exact counts per household size, or the free planner does the math for your family in about 60 seconds.