Knowing when to harvest potatoes from your backyard garden can be a bit tricky. This post will help you know when to harvest potatoes for a great crop of nice-sized spuds!
Every year I get questions posted about when to harvest potatoes. New gardeners always panic when the tops of their potato plants suddenly start to die back in the late summer and fall. I’m writing this post to help you know when to harvest potatoes for a good crop of mature potatoes that will store well and taste great!
Any time after they flower???
Roughly 6 to 8 weeks after you plant your potatoes the tops will flower. Technically any time after your potatoes flower you can start harvesting.
But if you harvest right after the plants flower the potatoes you harvest will be very small! These are what we call “new potatoes” and they will taste fantastic and will be very tender with thin skins. We always grow some early potatoes, specifically for this purpose. But if you want larger, mature potatoes that will last a long time in storage then you need to wait!
When to harvest potatoes – Tops dying back
Most potato varieties will mature in 90 to 120 days. This is the optimal time to keep them in the ground to get nice large potatoes. Since the potatoes are hiding in the ground, the first indication you get about when to harvest potatoes is when the tops start to die off.
When potato plants reach their final stage of development the “tops” or the above-ground foliage on the plants will first fall over and then slowly start to die off. All the energy from the plants is drawn down into the now mature potatoes and the tops will first lose structure and fall over, next, they will start to yellow and if left in the ground the tops will eventually die off completely and dry up.
I have found that the best time to harvest potatoes is when the tops look like this photo. The plants have fallen over and roughly 50% of the leaves have yellowed or withered. In our area, this seems to be the best time to harvest.
This is a photo of one of our patches that went a little too long this year. See how the tops are completely gone? This is a bit too long for your potatoes to be in the ground. It’s not the end of the world if you wait this long, but it does increase the risk of rotting. Also if you leave potatoes in the ground too long you risk the potatoes sprouting and growing new tops.
This is a shot of a patch of potatoes that is not ready to harvest yet. You can see some early signs of yellowing and the tops falling, but this patch could stay in the ground for at least another 3 weeks.
Make sure you check out the video that I filmed above. I was able to show you pictures of all 3 of our patches this year. They were all planted at different times so they are all in different stages of readiness for harvest.
Other potato-growing resources
Over the years I’ve written several posts on different aspects of growing potatoes. Here are some links to them to help you even more!