When Can You Harvest Potatoes After Planting?

Once the garden is planted, the season of anticipation begins. The ultimate question is "when can the harvest begin?" and this is particularly true of potatoes. With their tubers hidden underground, we cannot watch them grow until they are the perfect size and maturity.

Most potatoes are mature and full-sized 80 to 100 days after planting, depending on the variety. Creamer potatoes are harvested at 8 to 10 weeks, and early (sometimes called "new") potatoes can be harvested at 10 weeks.

How long does it take potatoes to grow after planting? There are many differing opinions on when is the best time to harvest potatoes, and this article will hopefully give you an idea of when you can eat your own spuds.

When To Harvest Full-Sized Potatoes

To have potatoes that you can store over winter, you want to wait until they are fully mature before harvesting. Generally, most potatoes are ready at 80 to 100, depending on the variety. Chitting, or sprouting, your potatoes prior to planting can help your potatoes mature a few weeks early.

The best way to know if your potatoes are ready to be harvested is to go off the tuber size itself. Gently feel under the plant to check how big the potatoes are. Leave them for a few more weeks if they feel too small. If they are a good size, it is time to harvest.

On average, you can expect 5 to 6 decent sized potatoes from each plant (or about 1kg).

When To Harvest Little Potatoes

At 8 weeks you can start "stealing" potatoes to have sweet little creamers. At 10 weeks, you can dig up your early, or new, potatoes.

These immature potatoes have not converted all of their sugar into starch, so they are not suitable for long-term storage. They are ideal for summer eating or keeping in the cupboard for a few weeks.

What About The Flowers?

Potato plants produce beautiful flowers that grow small berry-like fruits. These flowers indicate when the plant itself is mature, and not when the tubers underneath are ready. Some years your potato plants will not flower at all and still have an abundance of tubers, while other years there will be prolific flowers with not a single spud underneath.

Image by Carmen Edenhofer

Wait Until The Plant Dies Off

Waiting to harvest until the plant dies off is very common when growing potatoes, but not necessary. Potato plants are very frost-sensitive and will die off at the first nip. If you live in an area with a short growing season, waiting until the plant is frost-killed is pretty much a necessity to give the tubers the maximum amount of time in the ground. However, you can dig potatoes earlier than this, depending on what kind of potato you want.

Some seed companies suggest curing the tubers in the ground for two weeks after the plant has died off (or mechanically mowed). However, this practise is only beneficial in milder climates. In many areas, damp soil can cause the potatoes to sprout eyes or rot.