Idaho’s high desert climate with cool nights provides excellent conditions for beet development during summer months. Knowing the best time to plant beets in Idaho can make the difference between a bumper crop and a disappointing harvest. Beets thrive when soil temperatures are just right, and Idaho’s unique growing zones require a bit of planning.
This guide covers everything you need to know about timing your beet planting in the Gem State. You’ll learn about soil temps, frost dates, and variety selection for success.
Best Time To Plant Beets In Idaho
The best time to plant beets in Idaho is from early April through mid-July, depending on your specific location and elevation. For spring crops, aim for 2-4 weeks before the last expected frost. For fall harvests, plant 8-10 weeks before the first fall frost.
Beets are cool-season crops that handle light frosts well. They actually taste sweeter after a light frost because the plants convert starches to sugars. This makes timing flexible but still important.
Understanding Idaho’s Growing Zones
Idaho spans USDA hardiness zones 3 through 7. The southern part of the state (Boise, Twin Falls) is warmer, while northern areas (Coeur d’Alene, Sandpoint) and higher elevations are cooler. Your exact location matters.
- Zone 3-4 (northern Idaho, high mountains): Plant beets from late May to early June
- Zone 5 (central Idaho, lower valleys): Plant from mid-April to mid-June
- Zone 6-7 (southern Idaho, Treasure Valley): Plant from early April to early July
Check your specific frost dates using the Old Farmer’s Almanac or your local extension office. These dates are your best guide.
Soil Temperature Requirements
Beet seeds germinate best when soil temperatures are between 50°F and 85°F. The ideal range is 60-70°F. If the soil is too cold (below 40°F), seeds may rot before sprouting. If it’s too hot (above 85°F), germination drops significantly.
Use a soil thermometer to check. Insert it 2-3 inches deep in the morning. Wait until the soil consistently reaches at least 50°F before planting.
In Idaho, this usually happens:
- Southern Idaho: Late March to early April
- Central Idaho: Mid-April to early May
- Northern Idaho: Early to mid-May
Spring Planting Window
Spring is the most popular time to plant beets in Idaho. The key is to plant early enough to allow harvest before summer heat, but late enough to avoid a hard freeze.
For most of Idaho, the spring window opens about 2-4 weeks before the last frost date. In Boise (last frost around April 20), plant beets from late March to early April. In Coeur d’Alene (last frost around May 15), plant from late April to early May.
Beets take 50-70 days to mature depending on variety. Calculate backward from your first fall frost date to ensure you have enough growing time.
Succession Planting for Continuous Harvest
Don’t plant all your beets at once. Instead, plant small batches every 2-3 weeks. This gives you a steady supply of tender beets all season long. Start in spring and continue until mid-summer.
For example, in southern Idaho:
- First planting: Early April
- Second planting: Late April
- Third planting: Mid-May
- Fourth planting: Early June
- Final planting: Late June to early July
This method works well because beets don’t store long after harvest. Fresh beets taste much better than stored ones.
Fall Planting Window
Fall-planted beets are often sweeter and more tender than spring crops. The cooler temperatures and shorter days slow growth, concentrating sugars. Many Idaho gardeners prefer fall beets.
For fall harvest, plant beets 8-10 weeks before your first fall frost date. In southern Idaho (first frost around October 10), plant from early to mid-August. In northern Idaho (first frost around September 20), plant from mid-July to early August.
Fall beets can handle light frosts. In fact, a light frost improves their flavor. You can leave them in the ground until the soil freezes hard, usually late October or November.
Mulching for Extended Harvest
If you want to harvest beets into early winter, apply a thick layer of straw or leaves over the bed. This insulates the soil and prevents deep freezing. You can then dig beets as needed, even under snow.
This works best in southern Idaho where winters are milder. In northern Idaho, the ground freezes too deep for this method to work reliably.
Best Beet Varieties For Idaho
Not all beet varieties perform equally in Idaho’s climate. Some handle temperature swings better than others. Here are top picks:
- Detroit Dark Red: Classic variety, reliable, good for all zones
- Golden Beet: Sweeter, less earthy flavor, beautiful color
- Chioggia: Italian heirloom with red and white rings, mild flavor
- Early Wonder: Matures in 50 days, great for short seasons
- Bull’s Blood: Deep red leaves, good for greens and roots
- Touchstone Gold: Uniform golden roots, excellent for fall planting
For northern Idaho’s short season, choose early-maturing varieties like Early Wonder or Detroit Dark Red. For southern Idaho’s longer season, you can experiment with slower-maturing types.
Preparing Your Soil For Beets
Beets need loose, well-drained soil free of rocks and clods. Heavy clay soil causes misshapen roots. Idaho’s soil varies widely, from sandy loam in the south to heavy clay in some areas.
Test your soil pH. Beets prefer a pH between 6.0 and 7.0. If your soil is too acidic, add lime. If too alkaline, add sulfur. Idaho’s soil tends to be alkaline, especially in the south.
Work in 2-4 inches of compost before planting. This improves drainage and adds nutrients. Avoid fresh manure, which can cause forked roots. Use well-rotted compost instead.
Fertilizing Beets
Beets need phosphorus for root development and potassium for disease resistance. Too much nitrogen produces lush tops but small roots. Use a balanced fertilizer like 10-10-10 at planting time.
Side-dress with a low-nitrogen fertilizer (like 5-10-10) when plants are 4-6 inches tall. Avoid high-nitrogen fertilizers like blood meal or fish emulsion.
Planting Beets Step By Step
Follow these steps for successful beet planting in Idaho:
- Prepare the bed: Remove rocks, break up clods, rake smooth
- Sow seeds 1/2 inch deep, 1-2 inches apart in rows 12-18 inches apart
- Cover lightly with soil and water gently
- Keep soil moist until seeds germinate (5-10 days)
- Thin seedlings to 3-4 inches apart when they have 2-3 true leaves
- Mulch around plants to retain moisture and suppress weeds
Beet seeds are actually clusters of 2-4 seeds. This is why thinning is essential. If you don’t thin, you’ll get crowded, misshapen roots.
Watering Beets In Idaho’s Climate
Idaho’s dry climate means you must water beets regularly. Inconsistent watering causes tough, woody roots. Aim for 1-2 inches of water per week, including rainfall.
Water deeply and less frequently rather than shallow and often. This encourages deep root growth. Drip irrigation works best because it keeps foliage dry, reducing disease risk.
During hot spells in July and August, you may need to water every 2-3 days. Check soil moisture by sticking your finger 2 inches into the soil. If it feels dry, water.
Common Problems And Solutions
Idaho gardeners face a few beet-growing challenges. Here’s how to handle them:
- Poor germination: Soil too cold or too hot. Wait for proper temperatures.
- Misshapen roots: Rocky or compacted soil. Prepare bed thoroughly.
- Tough, woody beets: Heat stress or inconsistent watering. Plant at right time, water evenly.
- Leaf spots: Fungal disease from wet foliage. Water at soil level, improve air circulation.
- Bolting (going to seed): Temperature swings or stress. Plant at correct time, mulch to moderate soil temp.
Most problems stem from planting at the wrong time. Follow the timing guide above to avoid these issues.
Harvesting Beets At Peak Quality
Beets are ready to harvest when roots are 1-3 inches in diameter. Smaller beets are more tender. Larger beets can become woody, especially in hot weather.
Harvest by gently pulling or digging around the root. Don’t cut the taproot. Twist off the greens, leaving 1-2 inches of stem to prevent bleeding. Store beets in a plastic bag in the refrigerator for 2-3 weeks.
Beet greens are edible too. Harvest them when they’re 4-6 inches tall. Leave some leaves on the plant so roots continue growing.
Extending The Season With Cold Frames
If you want to plant even earlier in spring or later in fall, use a cold frame. This simple structure traps heat and protects plants from frost. You can plant beets 2-3 weeks earlier in spring and harvest 2-3 weeks later in fall.
Build a cold frame from old windows or buy a kit. Place it over your beet bed. Ventilate on warm days to prevent overheating. This works well in all parts of Idaho.
Frequently Asked Questions
Can I Plant Beets In Idaho In August?
Yes, in southern Idaho you can plant beets in early to mid-August for a fall harvest. In northern Idaho, August is too late because frost comes early. Stick to July planting for northern areas.
How Late Can I Plant Beets In Idaho?
In southern Idaho, you can plant beets as late as mid-July for a fall harvest. In central Idaho, late June is the cutoff. In northern Idaho, plant no later than early June for spring or mid-July for fall.
Do Beets Need Full Sun In Idaho?
Beets grow best in full sun (6-8 hours daily). They tolerate partial shade but produce smaller roots. In Idaho’s sunny climate, full sun is ideal for most locations.
Should I Soak Beet Seeds Before Planting?
Soaking beet seeds in water for 12-24 hours before planting can speed up germination. This is helpful in Idaho’s dry climate. Don’t soak longer than 24 hours or seeds may rot.
Can I Grow Beets In Containers In Idaho?
Yes, beets grow well in containers at least 8-12 inches deep. Use a quality potting mix and water regularly. Container beets need more frequent watering than in-ground plants, especially during Idaho’s hot summers.
Final Tips For Idaho Beet Growers
Start small if you’re new to growing beets. Plant a short row or a few containers. Learn how beets respond to your specific microclimate. Then expand next season.
Keep a garden journal. Note planting dates, weather conditions, and harvest results. This information becomes invaluable for future seasons. You’ll quickly learn the best time to plant beets in Idaho for your exact location.
Don’t forget to enjoy the greens. Beet greens are nutritious and delicious. Saute them with garlic and olive oil for a tasty side dish. You get two crops from one planting.
With proper timing and care, you’ll harvest sweet, tender beets from spring through fall. Idaho’s climate is perfect for this versatile root vegetable. Happy planting.