Few crops reward a little effort like potatoes do. Plant one pound of seed potatoes and you can dig three to five pounds of tubers back out, all from a vegetable that asks for loose soil, steady moisture, and a few rounds of mounding dirt up around the stems. Learning how to plant potatoes well comes down to a handful of decisions made early: where your seed comes from, whether you chit and cut it, when the soil is warm enough, how deep you bury the pieces, and how faithfully you hill. Get those right and the harvest more or less takes care of itself. This guide walks through every one of them, from the certified seed potato in your hand to the cured spuds in your storage bin.
Start with certified seed potatoes, not grocery-store spuds
A seed potato is not a seed at all. It is a small tuber, saved and grown specifically for replanting, that sprouts new plants from the dimpled buds on its skin called eyes. The single most important sourcing decision you will make is to buy certified disease-free seed potatoes from a garden center or seed company rather than planting potatoes from the supermarket.
There are two solid reasons for this. First, certified seed is inspected and guaranteed free of the bacterial, viral, and fungal diseases that haunt potatoes, scab, blight, and a long list of viruses among them. Once those pathogens enter your soil they can linger for years and ruin future crops, so starting clean is the only reliable way to keep a clean bed. Second, grocery-store potatoes are frequently treated with a sprout inhibitor to keep them from growing on the shelf. Plant one and it may simply sit in the ground and rot, or sprout weakly and late. Even untreated grocery potatoes carry unknown disease status.
If you are determined to grow a supermarket potato that has sprouted on its own, confine it to a container or grow bag whose soil you can discard at season’s end, never your main garden beds, so any disease it carries cannot spread.
When you buy, you are also choosing a maturity class, and it pays to match it to your goals:
- Early-season varieties mature in roughly 60 to 80 days, produce tender, thin-skinned tubers, and are the first to go in the ground. They are best eaten fresh and store only a few weeks. ‘Irish Cobbler’, ‘Red Norland’, and ‘Yukon Gold’ are popular choices.
- Mid- and late-season varieties take 100 to 130 days, develop thicker skins, and are the ones to grow if you want potatoes that keep for two to three months in storage. ‘Kennebec’, ‘Katahdin’, and ‘Red Pontiac’ are dependable keepers, and several offer resistance to scab or late blight, a worthwhile bonus.
Chit your seed potatoes to get a head start
Chitting, also called greensprouting or pre-sprouting, means deliberately encouraging your seed potatoes to grow short, sturdy sprouts before they go in the ground. It is optional, but it can shave a couple of weeks off the start of the season, which matters most to gardeners in short-summer climates trying to ripen a late variety before frost.
To chit, set the seed potatoes in a single layer, eye-end up, in a spot that is cool but bright, around 50 to 70 degrees Fahrenheit with indirect light. An egg carton or seed tray on a windowsill or in a cool, well-lit room works well. Light is the key difference from a dark pantry: it produces stubby, dark green-purple sprouts that resist breaking, whereas darkness and warmth produce long, pale, brittle shoots that snap off during planting and set the plant back.
Two to four weeks usually does it. Get the potatoes into the ground while the sprouts are still short, no more than an inch or so. Sprouts allowed to grow long are fragile and easily knocked off, and a plant that loses its first sprout produces a weaker, later crop.
Cut large seed potatoes, plant small ones whole
New plants grow from the eyes, and a single large seed potato carries several. Cutting it into pieces stretches your seed further and lifts your overall yield, so most gardeners cut anything larger than a hen’s egg and plant the small ones whole.
Cut each large seed potato into chunks roughly two inches across, about the size of a golf ball, making sure each piece keeps one to two eyes. A piece with no eye will never sprout; a piece with too little flesh lacks the stored energy to drive early growth. Use a clean, sharp knife.
The step people skip, and regret, is curing the cut surfaces. After cutting, spread the pieces in a single layer at room temperature for one to two days so the wounds dry and form a corky callus over the exposed flesh. That callus is a barrier against the soil-borne rots and diseases that pour into a fresh, wet wound the moment it hits damp ground. Skip curing and you risk pieces rotting before they ever sprout.
One caveat: if your soil is plagued by wireworms, root maggots, or similar pests, consider planting whole seed potatoes instead of cut pieces. Pests are drawn to the juicy exposed flesh of a cut tuber, and an intact skin offers more protection. As a rule of thumb, one pound of seed potatoes yields about eight to ten planting pieces.
When to plant potatoes
Potatoes are a cool-season crop, and the calendar is less reliable than a soil thermometer. Plant when the soil has reached about 45 to 55 degrees Fahrenheit, which usually falls two to three weeks before your average last frost date. In the North that often means late March through May; in the warm South, potatoes go in during late fall or winter.
Resist the urge to plant earlier into cold, waterlogged soil, where seed pieces sit and rot rather than grow. A useful field test: squeeze a handful of soil; if it packs into a sticky ball, it is too wet and cold to work, so wait. Many gardeners read local cues instead of a thermometer, the first dandelions blooming, or the snow melting off the hills.
Once the plants are up, potatoes tolerate a light frost, the foliage may blacken at the tips but the plant recovers. A hard freeze is another matter and can kill top growth back to the ground; every time that happens the plant must regrow, and the harvest comes later and smaller. If a hard freeze threatens emerged plants, mound soil or straw over them or cover them overnight.
Prepare the soil for loose roots and clean tubers
Potatoes form along the underground stem, so they need soil that is loose, deep, fertile, and free-draining, a sandy or loamy soil amended with plenty of compost is ideal. Heavy, compacted clay produces small, misshapen tubers and makes hilling and harvest miserable. Work the bed deeply and fold in well-rotted compost before planting; doing this in fall gives the soil time to settle and balance.
Two soil details set potatoes apart from most vegetables, and both come back to scab, the rough, corky skin patches caused by a soil organism that thrives in alkaline conditions:
- Aim for slightly acidic soil, around pH 5.0 to 6.0. Potatoes tolerate a wider range, but keeping the bed on the acidic side suppresses scab. Do not add lime to a potato bed; lime raises pH and invites scab.
- Avoid fresh manure. Fresh manure both activates scab and feeds excessive leafy growth at the expense of tubers. Use only well-composted manure or a balanced fertilizer instead.
On feeding: potatoes are moderate feeders that respond to a balanced fertilizer such as an organic 4-2-2 worked in at planting. Go easy on nitrogen. Too much produces lush, sprawling vines and disappointingly few potatoes underneath, and delays tuber formation.
Choose a planting method
There is no single correct way to plant potatoes. The right method depends on your soil, your space, and how much digging you want to do at harvest. Here is how the main approaches compare:
| Method | How it works | Best for | Trade-offs |
|---|---|---|---|
| Trench and hill (classic) | Plant 4-5 in. deep in a trench, then mound soil up around the stems through the season | In-ground beds, biggest yields | Most hilling labor; needs room between rows |
| Flat planting | Plant at shallow depth on level ground, hill with soil pulled from pathways | Loose, deep soil | Still requires diligent hilling |
| Deep digging (no-hill) | Plant 6-8 in. deep once so no mounding is needed | Low-maintenance gardeners | Slower emergence; harder harvest; rot risk in wet soil |
| Container / grow bag | Layer soil up the container as plants grow | Patios, no garden space | Smaller yields; dries out fast, needs frequent watering |
| Raised bed | Plant in deep, loose raised-bed soil and hill within the frame | Poor native soil, drainage | Limited depth caps how high you can hill |
| Straw / mulch | Set pieces just below the surface, bury under thick straw | Easy, clean, no-dig harvest | Needs lots of straw; can attract rodents |
For most gardeners with in-ground space, the trench-and-hill method gives the best balance of yield and reliability. Container and straw methods shine where soil is poor or absent, or when you want potatoes you can harvest without a fork.
Planting depth and spacing
Whatever method you choose, the geometry is similar. Dig a trench or individual holes about 4 to 6 inches deep (lean toward the shallower end in heavy soil, deeper in light, sandy soil). Set each cut piece or small whole potato cut-side down, eyes up.
- Spacing within the row: 10 to 12 inches apart for cut pieces. Give whole, larger seed potatoes a bit more room, 12 to 16 inches, since they grow into bigger plants. Small fingerlings can go as close as 8 inches.
- Row spacing: 18 to 36 inches between rows. Wider rows make hilling far easier, so favor more space if you have it.
Cover the pieces with 3 to 4 inches of soil and leave any trench only partly filled, you will add the rest of that soil as you hill. Expect plants to emerge in about two to three weeks.
Hilling: the step that makes or breaks the crop
Hilling, mounding loose soil up around the growing stems, is the most important ongoing task in growing potatoes, and the one beginners most often skip. It does two essential jobs.
First, it protects the tubers from light. Potatoes that are exposed to sunlight turn green and produce solanine, a bitter, mildly toxic compound. A green potato is not just unappealing; it should not be eaten. Burying the developing tubers under a hill of soil keeps them in the dark and edible.
Second, hilling increases yield. Potatoes form along the buried portion of the stem, not from the roots, so the more stem you cover with soil, the more length is available for tubers to set. More buried stem, more potatoes. Hilling also smothers weeds and can shield young shoots from a surprise late frost.
Here is the rhythm to follow:
- Start when plants are about 6 to 8 inches tall. Using a hoe, draw loose soil from both sides of the row up against the stems, burying the lower portion and leaving only the top 3 to 4 inches of foliage exposed. The first mound need only be a few inches high.
- Hill again every two to three weeks, or each time the plants gain another 6 inches, until they begin to flower. Most crops get two or three rounds, building to a mound roughly 10 to 12 inches high by the end.
- Stop hilling once flowering begins. That is when tuber formation kicks in, and further mounding adds little.
Watch for soil cracking or heaving near the base of the plants, that is a sign tubers are pushing toward the surface and you are overdue for another hilling. Keep the mounding material loose and well-draining; soil packed tight against the stems traps moisture and invites rot. Straw, shredded leaves, and compost all work in place of soil, and straw has the bonus of keeping the root zone cool and moist. In containers and grow bags, hilling simply means adding more mix as the plant climbs, until you reach the rim.
Watering and feeding through the season
Potatoes want consistent, even moisture, roughly 1 to 2 inches of water per week including rainfall. Erratic watering, drought followed by a heavy soak, causes knobby, cracked, or hollow tubers.
The critical window runs from flowering through the weeks that follow, when tubers are setting and bulking. Drought stress during this stretch hits yield harder than at any other time, so do not let the bed dry out then. As harvest nears and the vines begin to yellow, taper off watering to help the skins firm up. When you water, aim at the soil rather than the foliage, and water in the morning so leaves dry quickly. Wet leaves and standing water spread the fungal diseases covered below.
Harvest: new potatoes versus the main crop
Potatoes offer two harvests from the same planting.
New potatoes are immature, thin-skinned tubers harvested early for fresh eating. Begin checking a few weeks after the plants flower, or roughly 7 to 8 weeks after planting. Gently dig into the loose soil at the side of a hill and lift out a few small tubers without uprooting the plant, leaving the rest to keep growing. New potatoes are tender and delicious but do not store, eat them within days. Waxy varieties are best for this.
The main crop is for storage and is harvested when the vines have died back and lost most of their color, naturally at maturity or after a frost. To toughen the skins for storage, stop watering and either let the vines die fully or mow them off about two weeks before you dig. Then leave the tubers in the ground for those two weeks so the skins set, before lifting them with a digging fork on a dry day. Harvest before any hard freeze that could damage tubers lying near the surface.
Cure for storage by spreading the dug potatoes in a single layer in a cool, dark, humid, well-ventilated spot for one to two weeks, which heals minor nicks and firms the skin. Do not wash them, brush off the soil and store unwashed. Then keep them around 40 degrees Fahrenheit in the dark; a cool, dark cellar or closet is ideal. Light in storage will turn them green, the same solanine problem you guarded against by hilling.
Common pests and diseases, and how to prevent them
A handful of problems account for most potato troubles. Prevention, through clean certified seed, crop rotation, consistent moisture, and good airflow, beats cure in nearly every case.
Colorado potato beetle is the signature pest: a rounded, yellow-and-black-striped adult whose plump orange-red larvae can strip foliage fast. Scout the undersides of leaves for clusters of yellow-orange eggs and crush them; handpick and dispose of larvae and adults. Floating row cover laid over the plants early excludes the beetles entirely, and a straw mulch hosts beneficial insects that prey on the larvae. A spinosad insecticide is an option for heavy infestations.
Scab shows up as rough, corky, raised patches on the skin. The tubers are still edible, just unsightly, but the fix is in prevention: keep soil slightly acidic (pH 5.0 to 6.0), avoid lime and fresh manure, maintain even moisture, and choose scab-resistant varieties.
Early blight appears as dark brown spots with concentric rings on older, lower leaves, usually in warm, humid weather, weakening the plant gradually. Late blight is the far more destructive disease, the one behind historic famine, causing water-soaked dark lesions that spread rapidly through wet foliage and rot the tubers. For both, the defenses are the same: plant certified disease-free seed, give plants room for air to circulate, water at the soil line in the morning so leaves dry quickly, never work among wet plants, rotate where you grow potatoes each year, and remove and destroy infected plants promptly. Resistant varieties such as ‘Kennebec’ add another layer of protection.
Plant clean seed, plant at the right time into loose acidic soil, hill faithfully, and water steadily through flowering, and a single packet of certified seed potatoes will hand you a harvest worth many times what you put in. Start with one variety this season, master the hilling rhythm, and add an early type and a keeper next year so you have both fresh new potatoes in summer and stored spuds to carry you through winter.