Harvesting potatoes at the right moment is the difference between a crop that tastes superb and one that is tough, bitter or bland. Pick too early and you lose flavour; pick too late and you lose texture, and the plant slows down. This guide covers when to harvest potatoes — the signs that tell you when one is ready, how to pick it without damaging the plant, the best time of day to harvest, how often to check, what happens if fruit is left too long, and how to store the harvest, both for a few days and for months. The timing below uses the published range for this crop, 70–120 days to maturity, which varies by variety, climate and soil, so treat it as a guide and judge each plant by what you can see and feel.
Potatoes are a vegetable in the Solanaceae family, with frost-tolerant cold tolerance and moderate water needs. They need full sun and are usually direct sow. Knowing those basics helps you judge harvest time, because a plant that has been watered evenly and grown in the right conditions ripens evenly, while a stressed plant ripens unevenly and often disappoints. Keep a simple note of when you sowed and when you first picked — after one season you will have a record far more useful than any general guide. As with all the timings in this guide, these are broad published ranges, not exact dates for your garden, so check your local extension service for your area.
Potatoes at a glance
| Detail | Guidance |
|---|---|
| Days to maturity | 70–120 days |
| Family | Solanaceae |
| Category | vegetable |
| Cold tolerance | frost-tolerant |
| Water needs | moderate |
| Sun | full sun |
| Soil pH | 5.0–6.0 |
| Spacing | 12 inches |
| Sowing | direct sow |
If you are still growing this crop, the growing guide for potatoes covers soil, spacing, water and care in full, and the Zone 13 page for potatoes covers timing in a frost-free climate. The harvest date calculator can help you work out roughly when a sowing should be ready, and the vegetable yield estimator helps you plan how much to grow.
Signs that potatoes are ready to pick
The best harvest decisions are made with your eyes and hands, not with the calendar. Days to maturity is a useful starting point, but weather, variety and watering all shift it, so learn the signs for this crop and check plants regularly once the harvest window opens. For potatoes, the signs are:
- Tops die back: For maincrop potatoes, the tops yellow and die back when the tubers are ready. That is the clearest sign — the plant is telling you it has finished.
- A test dig: Dig up one plant with a fork and look at the tubers: they should be a good size for the variety, with firm, unbroken skins. If they are small, leave the rest another week or two.
- Skins set: Rub a tuber gently with your thumb: if the skin stays put, it has set and will store well. If the skin rubs off easily, the tubers need more time in the ground.
- Flowering is not the sign: Potato plants often flower well before the tubers are ready, so do not dig just because you see flowers — wait for the tops to die back or do a test dig.
The single most useful habit is to check plants every day or two once the first fruit starts to ripen, and to pick a test fruit if you are unsure. One test tells you more than a week of guessing. Taste it, look at it, feel it — and then pick the rest of the row at the same stage. If the test fruit is not ready, leave the row alone for a few days and test again. Over a season you will learn to read this crop at a glance, and harvesting will become quick and confident.
How to pick potatoes without damaging the plant
Use a garden fork, not a spade, and start digging a good distance from the plant so you do not spear the tubers. Lift the plant gently, then sift through the soil for every tuber — small ones hide easily. Let tubers dry on the soil surface for a few hours if the weather is dry, but do not leave them in the sun, which turns them green. Handle them gently: bruised potatoes rot in store.
Whatever the crop, the rules are the same: use clean, sharp tools, support the plant while you pick, pick in the cool of the morning when the produce is crisp, and never yank or tear. A clean cut heals fast; a tear leaves an open wound that disease can enter, and a damaged plant produces less for the rest of the season. Keep your tools clean between plants, wash your hands before handling food, and put harvested produce in a clean basket or trug rather than on the soil, where it picks up dirt and pests.
Best time of day and how often to pick
Pick in the morning, after the dew has dried but before the heat of the day, when the produce is cool, crisp and full of water. Produce picked in the heat of the day wilts fast and does not keep as well. Potatoes take 70–120 days to maturity, and the harvest is usually done in one go per planting, once the tops have died back. Early varieties can be dug while the tops are still green, for new potatoes — lift a plant, take the largest tubers, and leave the rest to grow.
Regular picking is not just about getting the best flavour — it is also how you keep the plant producing. Most fruiting vegetables slow down or stop setting new fruit when mature fruit is left hanging, because the plant has done its job. Picking regularly tells the plant to keep flowering, and in a frost-free climate that can mean months of extra harvests from the same plants.
What happens if potatoes are left too long
Left too long in wet soil, tubers can rot, split or be eaten by pests, and they may sprout again in the ground. Tubers left in the sun turn green, and green parts are bitter and should be cut away and not eaten. Dig promptly once the tops have died back.
The cost of leaving produce too long is not just one spoiled fruit. An over-mature fruit left on the plant can slow the whole plant down, attract pests that then move on to healthy fruit, and spread disease from rotting tissue. A daily or every-other-day check is the cheapest insurance in the garden: it takes a few minutes, and it catches problems while they are still small. If you do find over-mature fruit, remove it promptly — compost it if it is diseased, and use it in cooking if it is simply past its best.
How to store potatoes
Keep new potatoes in a cool, dark place and eat within a week or two. Do not wash them until you use them — soil left on protects the skins.
Maincrop potatoes store for months in a cool, dark, ventilated place — a paper sack or a box in a dark shed or cupboard. Check them regularly and remove any that are soft or sprouting, so one bad tuber does not spoil the rest. Do not store them in the fridge, and keep them away from onions, which can make them sprout.
A good rule for storage is to sort the harvest as you pick it: the best produce keeps longest, so store the firm, unblemished fruit and eat the damaged or softest pieces first. Check stored produce regularly and remove anything that softens or spoils, because one bad piece can spoil the rest. Label anything you freeze or dry with the crop and the date, so you know what you have and when to use it.
Succession sowing and continuous harvest
Plant in succession a few weeks apart for a spread of harvests, and grow early and maincrop varieties together for new potatoes first and storing potatoes later. In a frost-free zone, check your local extension service for the best planting windows in your area.
Succession sowing is the answer to the two most common harvest problems: a glut followed by nothing, and a crop that finishes all at once. Sow or plant a little, often, rather than a lot at once, and you will have a steady supply instead of a feast and a famine. Keep notes on what you sowed and when, so you can repeat the timing that worked and adjust the timing that did not.
Common harvesting mistakes
- Digging with a spade close to the plant and spearing the tubers.
- Leaving tubers in the sun, which turns them green.
- Digging too early, before the skins have set, so they do not store.
- Storing potatoes in the light or in the fridge, which spoils their flavour and texture.
Most harvesting mistakes come from the same place: guessing instead of looking, and leaving the garden alone for a week at the critical moment. A short daily check, a test fruit when you are unsure, and picking little and often will avoid nearly all of them.
Frequently asked questions
When are potatoes ready to dig?
When the tops yellow and die back, and a test dig shows tubers of a good size with skins that do not rub off. They take 70–120 days to maturity.
Can I dig potatoes before the tops die back?
Yes, for new potatoes — lift a plant while the tops are still green, take the largest tubers and eat them fresh. They will not store, so eat them within a week or two.
Why have my potatoes gone green?
They were exposed to light, usually by being left in the sun after digging or growing too near the surface. Green parts are bitter — cut them away generously and do not eat them.
How do I store potatoes for months?
In a cool, dark, ventilated place in a paper sack or box, unwashed. Check them regularly and remove any soft or sprouting tubers.
Do potatoes need full sun?
Yes — potatoes need full sun, and their water needs are moderate. Their soil should be loose and well drained, with a pH of 5.0–6.0.
Related guides
For more harvesting help, browse the guides hub, plan your next sowing with the planting calendar, and try the harvest date calculator and the vegetable yield estimator. If you are growing in a frost-free climate, the Zone 13 page for potatoes and the growing guide for potatoes are the best next reads. And as always, check your local extension service — local advice beats any general guide for your soil, your weather and your varieties.