Growing potatoes in planter bags is really easy. It means you can grow them in a small space and that you don’t have to dig the garden. In Auckland we can grow potatoes all year round and I like to stagger the planting so that I have a bag ready for harvesting every month or so. If you are not ready for another harvest, you can simply move the bag under the eaves of the house so that it stays dry and the potatoes will store well until you want them.
You will need planter bags, compost or container mix, seed potatoes and some potato food.
You can just plant the seed potatoes as they are, but many people like to let the potatoes start to sprout first. You will need to leave them in a bright place for about 3-4 weeks (although mine seem to sprout happily in the plastic bag in the shed).
Fill the planter bag with compost to about 15cm (about a quarter full). Place about 5 seed potatoes in the planter bag with the sprouts pointing upwards. Cover with about another 15cm of compost to about half full.
Once the potato shoots have come through and grown up above 3/4 full, top up the planter bag with compost to the 3/4 mark leaving the top of the shoots exposed. Fill the bag completely once the shoots have grown up further.
Water regularly but don’t let it get too wet or the potatoes will rot. Allow the plants to grow up and then they will start to die back. Once the plants have died back, you are ready to harvest your potatoes.
The picture on the planter bag packaging shows a person reaching into flaps in the side of the bags and pulling out spotlessly clean potatoes from within!! You may be able to pull out a few potatoes as you go, but they certainly won’t be clean. I generally harvest them all at once by gently removing soil from the top of the bag until you start to see new potatoes. Then you can remove them one by one, taking out more soil as you go.
I have an outdoor sink set up that is perfect for washing all the soil off the potatoes before I take them inside.
The amount of potatoes you get from a bag will depend on several things: variety of potato, time of year, fertiliser, water etc. But I usually get about a couple of kilos of potatoes from each bag.