If you are growing potatoes, they should be a fairly good size by early summer, and hopefully are looking healthy and green, with perhaps one or two flowers showing already. If so, you may be wondering when to harvest them…it depends a little on what type of potatoes you are growing.
When to Harvest Earlies
Earlies are usually ready for harvesting in early/mid July (first earlies) or mid July/August (second earlies). As soon as the flowers start to form, you should be good to go. Carefully pull one up and see what you’ve got hiding under the earth. If they are the right size, then your spuds are ready for harvesting.
When to Harvest Maincrops
Maincrops are, as a general rule, harvested towards the end of August through to November. For these, you want to wait for the leaves to start turning yellow before harvesting. Again, pull one up and check to be sure. (By the way, at this time of year, main crop potatoes could benefit from a liquid veg feed.)
Do I have to harvest them all right away?
Now, the chances are that you won’t want to eat all your potatoes at once, or you might not have time to harvest them all immediately. Fear not…all you need do is cut off the foliage and your potatoes will stop growing and will keep in the ground for a month (for earlies) or two months (main crop – providing it’s not frosty at the time you harvest them).
The only risk with this is a few underground munchkins eating away at them – wire worm are the most likely offenders. If you’re worried about this, you can harvest them and put them into a hessian sack. Keep them in a cool, dry, dark and airy place and they’ll keep for a month or so.
A final word of warning…don’t let your spuds get damaged by blight
Blight can become an issue, particularly in wet weather so keep a watchful eye. You’ll easily recognise blight as brown patches appearing on the leaves. Don’t panic, but try to catch it early! At the first sign of blight, either harvest your potatoes and store as above, or cut off all the foliage (and burn it on the bonfire to prevent it spreading) and let them sit in the ground for a week or two before digging them up.