I planted my potatoes back in late March. All was going well until we had a late frost, which blackened and killed the initial foliage. However, it's not that easy to stop a potato in its tracks, and with all this lovely warm, wet weather, my potatoes have sprung back to life. Now it's time to earth them up.
Earthing up is gardening jargon for part- burying your potato stems in a mound of soil.
It's important to earth up for two reasons:
- It increases the length of the underground potato producing stems, so you get a better yield.
- It protects the developing potatoes from exposure to light, which turns them green and poisonous.
Once the potato stems are about 10cm, it's time to earth up. You can do this in several stages, over a period of a few weeks.
Either loosen the soil between the potato rows with a fork, then using a rake or spade, draw the soil up and around the stems, until only the top leaves are poking through.
Or, if your potatoes are not planted in neat rows with a large enough gap between them to mound up in this way, fill a bucket of compost from your heap, and gently cover the stems until the last leaves are poking through. This method also works for potatoes planted in bags.
When frost is predicted, it's also a good idea to earth up, as this can prevent damage to the new shoots. Something that would have been useful for me to have put into practice a few weeks back!