What to Plant in August — Zone 3
Short growing season with harsh winters. Focus on cold-hardy and fast-maturing varieties.
Quick Answer
In zone 3 during August, late summer — fall garden planting begins in earnest alongside ongoing summer harvests. Your key tasks this month: plant fall crops: kale, spinach, lettuce, and radishes, harvest garlic when lower leaves brown, and begin harvesting tomatoes, peppers, and cucumbers.
August Gardening Tasks for Zone 3
August is late summer — fall garden planting begins in earnest alongside ongoing summer harvests. Zone 3 has a frost-free window from June 1 – Sept 1, which shapes what you can plant and when. Here is your complete task list:
Plant Guides for This Month
These plants are mentioned in your August tasks. Read their full growing guides for detailed planting instructions:
Tomato
America's most popular garden vegetable, tomatoes come in thousands of varieties…
Lettuce
Lettuce is the perfect beginner crop—fast-growing, forgiving, and endlessly vers…
Cucumber
Cucumbers are summer garden staples that grow fast and produce abundantly. Wheth…
Garlic
Garlic is the gardener's most patient reward. Planted in autumn and harvested th…
Spinach
Spinach is a cool-weather superstar packed with iron and vitamins. It grows quic…
Kale
Kale is the hardiest green in the garden—thriving in cold weather that kills mos…
Radish
Radishes are the fastest crop in the garden—ready in under a month from seed. Th…
Helpful Guides for August
These gardening guides are especially useful this time of year:
- Seed Starting Indoors — essential if you're starting transplants this month
- Companion Planting Guide — plan your layout for maximum yield
- Organic Pest Control — prepare defenses as the season progresses
- Building Better Soil — start any month to improve next season's harvests
- Pest & Disease Library — identify and solve common garden problems organically
- Browse All Plant Guides — detailed growing instructions for every crop
Frequently Asked Questions
What should I plant in August in zone 3?
In zone 3 during August, focus on: Plant fall crops: kale, spinach, lettuce, and radishes. Harvest garlic when lower leaves brown. Begin harvesting tomatoes, peppers, and cucumbers. The frost-free period for zone 3 is June 1 – Sept 1.
Is it too late to plant in August in zone 3?
August is a productive month in zone 3. Short growing season with harsh winters. Focus on cold-hardy and fast-maturing varieties. Check each crop's days to maturity against your remaining frost-free window (June 1 – Sept 1).
What is USDA zone 3?
USDA Zone 3 has a frost-free growing season from approximately June 1 – Sept 1. Short growing season with harsh winters. Focus on cold-hardy and fast-maturing varieties.