Tennessee’s long growing season supports both an early spring and a late summer potato planting. Knowing the best time to plant potatoes in tennessee is key to a big harvest. You can get two crops each year if you time it right.
Potatoes are a cool-weather crop. They stop growing when the soil gets too hot. That is why you need to plant them early enough so they mature before summer heat sets in. For a fall crop, you plant in late summer so they grow during the cooler autumn weeks.
Best Time To Plant Potatoes In Tennessee
The best time to plant potatoes in tennessee is about two to four weeks before the last spring frost. For most of the state, that means mid-March to early April. For the fall crop, plant from late July to mid-August.
Your exact planting date depends on where you live in Tennessee. The state has three main growing zones: West, Middle, and East Tennessee. Each zone has a slightly different climate.
Spring Planting Window By Region
West Tennessee (Memphis area) is warmer. You can plant as early as mid-March. The last frost usually happens by late March.
Middle Tennessee (Nashville area) has a later frost. Plant from late March to early April. The soil warms up slower here.
East Tennessee (Knoxville area) is cooler. Wait until early to mid-April. The mountains can have frost into late April.
Fall Planting Window By Region
For a fall crop, you want the potatoes to mature before the first hard frost. Count back 90 to 120 days from your first fall frost date.
- West Tennessee: Plant from late July to early August
- Middle Tennessee: Plant from late July to mid-August
- East Tennessee: Plant from mid-July to early August
Fall potatoes are often sweeter. The cooler weather helps them develop better flavor. They also store longer than spring potatoes.
Soil Temperature Requirements
Soil temperature matters more than the calendar date. Potatoes need soil that is at least 45°F (7°C) at planting depth. If the soil is too cold, the seed pieces will rot.
Ideal soil temperature for potato growth is between 60°F and 70°F. Use a soil thermometer to check. Insert it four inches deep in the morning.
How To Warm Soil Faster
If your soil is still cold, you can warm it up. Cover the planting bed with black plastic for two weeks before planting. This can raise the soil temperature by 5 to 10 degrees.
Raised beds also warm up faster than ground soil. They drain better too, which helps prevent rot.
Choosing The Right Potato Varieties
Not all potatoes grow well in Tennessee. You need varieties that mature before the heat arrives. Look for early or mid-season types.
Best Varieties For Tennessee
- Yukon Gold: A mid-season potato with buttery flavor. Matures in 70 to 90 days.
- Red Pontiac: An early variety. Good for boiling. Matures in 80 to 100 days.
- Kennebec: A late-season potato that stores well. Matures in 90 to 110 days.
- Irish Cobbler: An early heirloom variety. Matures in 70 to 80 days.
- Purple Viking: A colorful mid-season potato. Matures in 80 to 95 days.
For fall planting, choose varieties that mature in 90 to 110 days. This gives them enough time before frost.
Preparing Seed Potatoes
You do not plant whole potatoes. You cut them into pieces. Each piece should have at least one eye. The eye is where the sprout grows.
Step-By-Step Seed Preparation
- Buy certified seed potatoes from a garden center. Do not use grocery store potatoes. They may carry diseases.
- Cut the potatoes into pieces about 1.5 to 2 inches wide. Each piece should have one or two eyes.
- Let the cut pieces dry for 24 to 48 hours. This forms a callus over the cut surface. It prevents rot.
- If you want earlier growth, you can chit the seed pieces. Place them in a bright, cool spot for two weeks. Sprouts will form.
Small seed potatoes can be planted whole. Just make sure they are not too big. A whole potato the size of an egg works fine.
Planting Depth And Spacing
Planting depth affects how many potatoes you get. Deeper planting usually gives more potatoes, but they take longer to emerge.
Correct Planting Method
Dig a trench about 4 to 6 inches deep. Place the seed pieces with the eyes facing up. Space them 12 inches apart in the row.
Rows should be 2 to 3 feet apart. This gives the plants room to grow and makes harvesting easier.
Cover the seed pieces with 3 to 4 inches of soil. Do not fill the trench completely. Leave it slightly mounded.
Hilling Up Potatoes
As the plants grow, you need to hill them. Hilling means pulling soil up around the stems. This prevents the potatoes from turning green from sun exposure.
- When the plants are 6 to 8 inches tall, hill them. Pull soil from between the rows up to the stems.
- Leave about 4 inches of the plant exposed.
- Repeat hilling every two to three weeks until the plants flower.
Hilling also encourages more tuber growth. The buried stems produce more roots, which become potatoes.
Watering And Fertilizing
Potatoes need consistent moisture. Too little water and the tubers are small. Too much water and they rot.
Watering Schedule
Water deeply once a week. Give the plants about 1 to 2 inches of water per week. If it rains, adjust accordingly.
Stop watering two weeks before harvest. This helps the skins set and prevents rot during storage.
Fertilizer Needs
Potatoes need nitrogen, phosphorus, and potassium. Use a balanced fertilizer like 10-10-10. Apply it at planting time.
Side-dress with fertilizer when the plants are 6 inches tall. Sprinkle a small amount along the row and water it in.
Do not use too much nitrogen. It will make big leaves but small potatoes. Focus on phosphorus and potassium for tuber growth.
Common Pests And Diseases
Tennessee has several pests that attack potatoes. The most common are Colorado potato beetles, aphids, and wireworms.
Colorado Potato Beetle
These beetles are yellow with black stripes. They eat the leaves. Hand pick them off or use neem oil spray. Rotate your crops each year to reduce their numbers.
Aphids
Aphids are small green insects. They suck sap from the leaves. They can spread viruses. Use insecticidal soap or a strong water spray to knock them off.
Wireworms
Wireworms live in the soil. They bore into the potatoes. They are hard to control. Plant potatoes in a spot that was not in grass the year before.
Diseases
Late blight and early blight are common in Tennessee. Late blight causes dark spots on leaves and tubers. Early blight causes brown spots with rings.
To prevent blight, plant disease-resistant varieties. Space plants well for air circulation. Water at the base, not on the leaves.
Harvesting Potatoes
You can harvest new potatoes early. These are small, tender potatoes. Harvest them when the plants start to flower. Gently dig around the roots to find them.
For full-sized potatoes, wait until the plants die back. The leaves will turn yellow and fall over. Then wait two more weeks before digging.
How To Harvest
- Use a garden fork to loosen the soil. Start a foot away from the plant to avoid stabbing the potatoes.
- Gently lift the plant. Shake off the soil.
- Pick up all the potatoes. Even small ones. Leftover potatoes can grow next year and become weeds.
Harvest on a dry day. Wet potatoes are harder to clean and store poorly.
Curing And Storing Potatoes
Curing helps the skins thicken. This makes the potatoes last longer. Do not wash them before curing. Just brush off the loose soil.
Curing Process
Place the potatoes in a dark, humid spot for 10 to 14 days. The temperature should be 50°F to 60°F. A garage or basement works well.
After curing, sort the potatoes. Remove any that are damaged or have soft spots. These will spoil quickly.
Storage Conditions
Store cured potatoes in a cool, dark, dry place. Ideal temperature is 40°F to 50°F. Do not store them in the refrigerator. The cold turns the starch to sugar.
Keep them in a paper bag or a cardboard box. Do not use plastic bags. They trap moisture and cause rot.
Check the potatoes every few weeks. Remove any that start to sprout or rot.
Tips For A Successful Fall Crop
Fall planting is a bit different from spring. The weather is warmer when you plant. You need to keep the soil moist for germination.
Fall Planting Tips
- Mulch the soil after planting. This keeps it cool and moist.
- Water more frequently if it is hot. The soil dries out fast in late summer.
- Watch for pests. Colorado potato beetles are still active in late summer.
- Harvest before the first hard frost. Cover the plants with a row cover if frost is predicted.
Fall potatoes often have a better texture. They are firmer and less watery than spring potatoes. They also store better because the weather is cooler.
Common Mistakes To Avoid
Many gardeners make the same mistakes. Here are the most common ones and how to avoid them.
Planting Too Early
If you plant when the soil is too cold, the seed pieces rot. Wait until the soil is at least 45°F. Check with a thermometer.
Planting Too Late
If you plant too late in spring, the potatoes will not mature before the heat. They will be small. Stick to the recommended dates for your region.
Using Grocery Store Potatoes
Store potatoes may carry diseases. They are also treated to prevent sprouting. Use certified seed potatoes from a garden center.
Overwatering
Too much water causes rot. Water deeply but infrequently. Let the soil dry out between waterings.
Not Hilling
If you do not hill, the potatoes near the surface turn green. Green potatoes are toxic. Hill regularly to keep them covered.
Frequently Asked Questions
Can I plant potatoes in Tennessee in the summer?
Summer is too hot for potatoes. They stop growing when the soil is above 80°F. Stick to spring and fall planting.
What is the latest I can plant potatoes in Tennessee?
For spring, the latest is mid-April in most areas. For fall, the latest is mid-August. Check your first frost date.
Do potatoes need full sun in Tennessee?
Yes, they need at least 6 to 8 hours of direct sun per day. Partial shade will reduce your harvest.
How long do potatoes take to grow in Tennessee?
Most varieties take 70 to 110 days from planting to harvest. Early varieties are faster. Late varieties take longer.
Can I grow potatoes in containers in Tennessee?
Yes, containers work well. Use a 10-gallon pot or a grow bag. Fill it with loose, well-draining soil. Water more often because containers dry out faster.
Final Thoughts On Planting Potatoes In Tennessee
Timing is everything for potatoes in Tennessee. Plant too early and they rot. Plant too late and they burn in the heat. Follow the guidelines for your region and you will get a good harvest.
Remember to check soil temperature, not just the calendar. Use certified seed potatoes. Hill the plants regularly. Water consistently but not too much.
With two planting seasons each year, you can enjoy fresh potatoes from spring through fall. Store them properly and you can have homegrown potatoes all winter.
Start planning your potato patch now. Mark your calendar for the right planting dates. Your efforts will pay off with a bountiful harvest of delicious, homegrown potatoes.