What are seed potatoes, and why not use grocery store potatoes?
Seed potatoes are tubers grown and inspected for planting. Certified seed lowers the risk of bringing disease into your soil. Grocery potatoes may be treated to stop sprouting and can carry disease, so they are a poor choice for planting.
Order or buy seed from a reputable source and ask your extension office which varieties suit your region and season length. Early, mid and late types mature at different times, which spreads out your harvest.
Chitting, or letting seed potatoes sprout in light before planting, is optional but gives some gardeners an earlier start. Set tubers in a cool, bright place until short, sturdy sprouts form, and handle them gently so the sprouts do not break off.
- Certified seed from a trusted source
- Cut pieces with one or two eyes
- Heal cut surfaces before planting
When should I plant potatoes?
Potatoes are a cool-season crop that tolerates light spring frosts but not soggy, cold soil. Plant a few weeks before your average last frost date, once soil can be worked and is no longer waterlogged. Your extension office can give local dates and soil temperature guidance.
In warm regions, planting schedules shift earlier, and some areas grow a second crop in fall. Count days to maturity from the variety description and compare it with your first fall frost.
Plan where potatoes will grow in relation to other crops. They share diseases with tomatoes, peppers and eggplant, so avoid planting them in a bed those crops used recently, and rotate to unrelated crops in the following years.
- Soil workable and not soggy
- Certified seed from a trusted source
- Variety matched to season length
- Frost dates from your extension office
How do I cut, plant and space seed potatoes?
Large seed potatoes can be cut into pieces with at least one or two eyes, then left to heal for a day or two before planting. Small whole tubers need no cutting. Use a clean knife and discard any rotten pieces.
Plant pieces cut side down at the depth and spacing given in your extension publication, in loose, well-drained soil. Potatoes do not need rich soil, and fresh manure can encourage scab and rot.
Crowding reduces tuber size, so follow spacing guidelines and leave room for hilling.
What is hilling and why does it matter?
As plants grow, soil is drawn up around the stems to cover the developing tubers. Hilling keeps tubers covered, which matters because exposed tubers turn green. Green potato skin and flesh should not be eaten, so cut away any green areas generously or discard the tuber.
Mulching with straw can serve a similar role. Add soil or mulch in stages as plants grow, taking care not to bury all foliage at once.
Containers and grow bags work for small spaces. Use a large container with drainage holes, add soil as plants grow and water carefully, since containers dry out quickly in warm weather.
How much water and feeding do potatoes need?
Steady moisture through tuber formation gives a smooth crop. Dry spells followed by heavy water can cause cracks and misshapen tubers. Avoid wetting leaves late in the day, since wet foliage invites blight.
Use a soil test to guide feeding. Too much nitrogen gives lots of vines and few tubers, and a soil pH that is too high can encourage scab. Ask your extension office about local recommendations.
Keep notes of varieties, planting dates and yields by bed. Over a few seasons, your records show which varieties suit your soil and climate and which are not worth the space.
What pests and diseases should I look for?
Colorado potato beetles, flea beetles, aphids, scab and blight are the common issues. Check leaves regularly, hand-pick beetles and egg masses, and remove diseased plants promptly.
Late blight can spread fast in cool, wet weather and affects tomatoes too. If you suspect it, contact your extension office quickly and ask how to dispose of plants. Rotate away from tomatoes, peppers and eggplant.
When and how do I harvest, cure and store potatoes?
New potatoes can be dug while plants are still green. For storage, wait until vines die back and skins are set, then dig carefully on a dry day. Handle gently to avoid bruises, and do not wash.
Cure tubers in a cool, dark, humid place for a short period, then store them in a cool, dark, ventilated location. Light causes greening, so keep them covered. Check regularly and remove any soft or rotting tubers right away.
Key takeaways
- Use certified seed, not grocery potatoes
- Plant in cool, workable soil
- Hill plants to keep tubers covered
- Cure, store dark and discard green or rotten tubers
Sources and further reading
Last reviewed: November 12, 2026. Written by the Homestead & Small Farm Editorial Team. See our editorial policy.