Planting Guides
When to Plant Vegetables in Spokane: Zone 6b Dates + Varieties
Plant vegetables in Spokane around the May 13 last frost. Start cool-season crops in April, set out warm-season transplants late May, and work with Zone 6b's 160-day window.
— Image © PlantReference.org 2026
Quick Answer
Spokane's last frost averages May 13. Start cool crops in April, transplant warm-season vegetables after May 20-30 when soil hits 60°F.
TL;DR
Spokane sits in USDA Zone 6b with a May 13 average last frost and October 5 first frost—giving you roughly 160 frost-free days. Start cool-season crops indoors in March, direct-sow peas, lettuce, and spinach in early April, and hold warm-season transplants until late May or early June when soil hits 60°F. Choose short-season varieties like Solanum lycopersicum 'Glacier' and Capsicum annuum 'Yankee Bell' that mature within Spokane's narrow inland window.
On This Page
Frequently Asked Questions
The average last spring frost in Spokane is May 13, with the average first fall frost on October 5, giving roughly 160 frost-free days in USDA Zone 6b. Hard freezes through late May are not unusual, so most Spokane gardeners hold warm-season transplants until May 20-30 to be safe. The first fall frost can arrive earlier than October 5 in some years—keep row covers ready from mid-September on, and watch the forecast carefully through Memorial Day in spring. A single overnight freeze takes out unprotected tomatoes, peppers, and basil.
Spokane's strongest vegetables are short-season tomatoes, sweet peppers, kale, broccoli, peas, lettuce, carrots, and long-day onions. Pick varieties under 70 days to maturity for fruiting crops. Solanum lycopersicum 'Glacier' tomatoes and Capsicum annuum 'Yankee Bell' peppers are reliable Spokane producers. Brassicas like Brassica oleracea 'Lacinato' kale and Brassica oleracea 'Calabrese' broccoli actually improve in flavor with light fall frosts, and the cool spring lets Pisum sativum 'Oregon Sugar Pod II' peas thrive through June before summer heat shuts them down.
Start tomato seeds indoors in late March to early April, about 6-7 weeks before your planned May 20-30 transplant date. Keep soil temperature between 70-85°F (21-29°C) for fastest germination, and place seedlings under grow lights for 14-16 hours daily once they emerge to prevent leggy stretching. Starting earlier than late March risks root-bound transplants that never fully recover. If you only have window light, expect leggier plants and consider grow lights as the worthwhile investment for Spokane tomato success. [[When to Plant Tomatoes in Portland: Complete Guide + Best Varieties for Zone 8b]]
Spokane native soils commonly run pH 7.5-8.0, which locks up iron and manganese and triggers leaf yellowing in many vegetables. The long-term fix is working elemental sulfur into beds each fall at 2-4 lbs per 100 square feet for a half-point pH drop. Retest annually and continue applications until you reach pH 6.5-7.0. In the short term, foliar sprays of chelated iron green up chlorotic plants within a week. Raised beds filled with imported compost-rich soil bypass the problem entirely and warm faster in spring, which matters with Spokane's narrow growing window. [[Raised Bed Soil pH Problems: Testing, Adjusting, and Maintaining Balance]]
Yes, but be selective. Spokane's summer heat is actually higher than Seattle's, so melons, eggplant, and full-season peppers are more achievable here than west of the Cascades. The constraint is the shorter season—pick varieties under 80 days to maturity and start transplants indoors in early April. Use black plastic mulch to pre-warm beds and Wall-o-Water cloches for the first 3-4 weeks after transplanting to protect against late spring freezes. With this setup, varieties like 'Minnesota Midget' melon and Capsicum annuum 'Sweet Banana' pepper ripen reliably in most Spokane summers.
Plant garlic cloves in Spokane between September 15 and October 5, about 4-6 weeks before the ground freezes. This gives roots time to establish before dormancy. Mulch heavily—3-4 inches (7.5-10 cm) of straw or shredded leaves—to insulate cloves over Spokane's cold winters. Hardneck varieties like Allium sativum 'Music' (AL-ee-um sa-TY-vum) handle Spokane's winters well and produce flavorful scapes in June. Harvest in early to mid-July when the lower half of leaves yellow but several upper leaves remain green. Cure for 2 weeks in a dry shaded spot before storing.
Spokane vegetable gardens need roughly 1-1.5 inches (2.5-3.8 cm) of water per week during peak summer (June-September), increasing during heat waves above 95°F (35°C). Drip irrigation on a timer is the most efficient delivery method and keeps foliage dry to reduce disease. Mulch heavily with 2-3 inches of straw, wood chips, or shredded leaves to cut irrigation needs by roughly half. Spokane summers are functionally a desert with under half an inch of July rain, so consistent watering is non-negotiable for productive vegetable beds. [[5 Best Drip Irrigation Kits for Raised Beds (Tested for Easy Installation)]]
New Plant Daily
Think you know your plants?
Test your botanical knowledge with a new plant identification challenge every day. Build your streak, learn fascinating plant facts, and become a plant identification expert!
Build your streakOne chance per dayLearn as you play
Tagged with
Written By
L
Lily is a Master Gardener and high-desert homesteader outside Boise. She and her husband moved to Idaho from the Bay Area and had to completely relearn gardening for a climate with alkaline soil, intense sun, hard freezes, and limited water. Lily now grows a large vegetable garden, maintains a small orchard of cold-hardy fruit trees, and raises cut flowers for the local farmers market. She writes about the specific challenges of intermountain gardening—short seasons, temperature swings, and the importance of soil amendment in high-pH soils. Lily is honest about the learning curve: high-desert gardening is humbling, and she thinks more gardening writers should admit when conditions are genuinely difficult.
