When to Harvest Potatoes: New Potatoes vs Storage Potatoes
Knowing when to harvest potatoes depends on how they will be used. Iowa State University Extension notes new potatoes are dug while plants are still green plus tubers are over 1 inch across. Potatoes grown for storage are harvested after the vines have died plus the crop is mature, with skins that no longer rub off.
The short answer
Dig new potatoes while the plants are still green plus tubers are larger than 1 inch across, then use them soon since they do not store well. Dig storage potatoes after the vines die. If skins are thin plus rub off easily, wait several more days. Rest storage potatoes for 2 weeks at 50 to 60 F.
When are new potatoes ready?
Iowa State University Extension notes new potatoes are small, immature tubers dug while the plants are still green, once tubers are greater than 1 inch in diameter. They should be used right away because they do not store well.
| Harvest | Timing | Next step |
|---|---|---|
| New potatoes | Vines green, tubers over 1 inch | Use right away |
| Storage potatoes | Vines dead, crop mature | Cure, then store |
| Skin check | Dig 1 or 2 hills after vines die | Wait if skins rub off |
| Tops still green at season end | Cut or pull them | At least 7 days before harvest |
| Curing | 50 to 60 F, 85 to 90 percent humidity | 2 weeks |
| Storage | 38 F, 95 percent humidity | Dark place |
Source: Iowa State University Extension plus University of Maine Cooperative Extension.
How do you know skins have set?
Iowa State University Extension suggests digging 1 or 2 hills after the plants have died. If skins on the tubers are thin plus rub off easily, the crop is not fully mature, so allow several more days. University of Maine Cooperative Extension suggests cutting or pulling tops at least seven days before harvest if they have not died.
How should potatoes be rested?
Iowa State University Extension suggests resting tubers at 50 to 60 F with 85 to 90 percent relative humidity for 2 weeks before storage. The resting period lets minor cuts plus bruises mend, plus the skin thickens. Avoid bruising, skinning or cutting tubers while digging, plus use damaged ones soon.
How to: step by step
- Decide whether you want new or storage potatoes.
- For new potatoes, dig while vines are green.
- For storage, wait for vine dieback.
- Dig 1 or 2 hills plus rub a tuber skin.
- Lift tubers gently plus move them out of light.
- Rest tubers 2 weeks, then store cool plus dark.
Troubleshooting
Skins rub off: crop not mature. Iowa State University Extension suggests a longer wait.
Green patches: light exposure. University of Maine Cooperative Extension suggests getting tubers out of light after harvest.
Bruised tubers: rough handling. University of Maine Cooperative Extension notes potatoes bruise, so handle them like eggs.
For related reading see when to harvest outdoor cannabis, checking soil moisture by feel plus cannabis taproot vs fibrous roots. Kind Seed Co also stocks cannabis seeds.
Sources
- When should I harvest potatoes?, Iowa State University Extension plus Outreach
- Potatoes, UF/IFAS Gardening Solutions
- Potato facts: growing potatoes in the home garden (Bulletin 2077), University of Maine Cooperative Extension
FAQ
How long do potatoes take to grow?
It depends on variety plus region. UF/IFAS notes Florida gardeners plant across the state in January, plus potatoes grown in perlite are usually ready in a few months. University of Maine Cooperative Extension notes potatoes are traditionally harvested at the end of the growing season, often after a frost.
Can I leave potatoes in the ground?
Briefly. Iowa State University Extension notes storage potatoes stay in the ground until vines die plus skins set, often several more days after dieback. University of Maine Cooperative Extension suggests cutting or pulling green tops at least seven days before harvest, then lifting tubers with a tool that does not damage them.
How do I store potatoes?
University of Maine Cooperative Extension suggests storing potatoes in a cool, moist, dark place, ideally 38 F with 95 percent humidity. A cool, damp basement often works if the floor stays dry. Store only intact tubers plus skip diseased or damaged ones. Rest them first for 2 weeks at 50 to 60 F.
Why are my potatoes green?
Light exposure. University of Maine Cooperative Extension suggests getting harvested potatoes out of the light to avoid greening plus storing them in a dark place. In the garden, it suggests hilling soil into a mound over the row once plants are about six inches tall, with up to three hillings depending on conditions.
Should damaged potatoes be stored?
No. Iowa State University Extension notes damaged potatoes should be used as soon as possible, plus suggests avoiding bruising, skinning or cutting tubers during harvest. University of Maine Cooperative Extension suggests selecting only intact tubers for long term storage plus handling potatoes like eggs, since they bruise easily.
