8 May 2014
Growing Potatoes in Containers
One of the best things about vegetable gardening is eating new potatoes fresh from your garden. You might think you haven't enough room, but potatoes are easy to grow in bags or containers. You can use purpose-made potato bags, plastic containers or even old polythene compost bags, though the larger the container, the more potatoes you can plant.
Make sure that your container has drainage holes in the bottom, then add crock, gravel or broken polystyrene to provide a drainage layer. Next put 6-8 inches (15cm-20cm) of good quality potting compost, or multipurpose compost mixed 50/50 with sharp sand in your container. Adding well rotted farmyard manure or homemade compost will help to hold moisture, and will also add nutrients which will boost your crop.
I usually just grow first earlies in containers, but you should be able to grow any type of potato if your container is large enough.
Place 1, 3 or 5 chitted seed potatoes on top of the compost, depending on the surface area of your containers, then cover them with another 4-6 inches (10-15 cm) of compost. As a guide, use 1 tuber for a 10 inch (25cm) wide container, 3 tubers in an 18 inch (40cm) container or 5 tubers for a dustbin sized container.
You should see your potato plants starting to appear after a couple of weeks, and when this happens keep covering them in more compost, until you are a couple of inches below the top of the container. This process equates to ‘earthing up’ potatoes grown in the ground, and protects the tubers from light, and the potato plants from frost.
As they are growing, you will need to keep your potatoes well watered. You may want to apply a liquid plant food to the water as you go along, but don't do this if you have already added plant food to the compost, as you can over-feed your crop.
When growing potatoes in containers you need to pay close attention to watering, as soil in containers dries out more quickly than in the ground. However, you can over-water your crop, so be careful. Water the soil rather than the plant leaves, as it will have more effect this way. You may even need to water morning and evening if you have tubers in your containers in the middle of summer.
And now the time you have been waiting for! First and second earlies can be harvested when the plants stop flowering. Remove the top off the plant, dig out some of the compost, and take out as many potatoes as you need. The rest you can leave in the soil for up to 4 weeks. Maincrop potatoes should be harvested when the tops of the plants drop and wither away - usually towards the end of September. Remove the potatoes from the soil, and allow them to dry before storing them away for winter.
I hope you enjoy a bumper crop of beautiful new potatoes.