What I love about potatoes is that they can grow almost anywhere, even with limited space. You can grow them in reusable potato growbags or sacks(mumasaka) which you can find anywhere. These are easy to place on a balcony, patio, greenhouse or just in your backyard. What’s more, they make harvesting pretty easy!
What you need to grow potatoes in bags
Your choice of seed is very important especially if you’re growing potatoes for the first time. It’s best to plant an early varieties such as Duke of York, Homeguard or Orla because you can harvest them earlier than maincrop varieties, giving you a better yield.
Use a good multi-purpose compost or a mixture of 60 compost to 40 topsoil (avoid manure). You can also use fertilizer but this is optional. However, for is maximum yield, it’s recommended. To start with, choose an area with at least 6 hrs of direct sun per day to place your potato bags/sacks/planter in. Make sure the containers you are using have good drainage.
Most potatoes should be planted between November to February. However, with a good water supply, they can planted at anytime of the year while avoiding the colder months.
Chit your potatoes
Chit the potatoes (sprout seed potatoes before planting) to produce sturdy shoots. This encourages faster establishment and helps them grow better. You can chit by leaving the seed in an open egg tray about 4 weeks allowing them to sprout. The place should be cool and have light to prevent rotting.
Keep a eye on the potatoes and place them so that the parts with the most ‘eyes’ face upwards. The potato’s eyes are the small buds in the skin where the new shoots sprout from.
Fill the bags to about 20cm with your mixture of top soil/compost or multi-purpose compost. Then, spread 3 or 4 seed potatoes evenly on top of the compost and layer with another 10cm of compost mix.
When the plants start growing, gently cover the shoots with more of the compost mix until it reaches just below the top of the bag/sack. Don’t forget to keep the compost moist but not soggy. However, when the temperature is high, you can water heavily than lightly because the water has to go down to the lower roots. Keep an eye out for pests, especially chewing insects which can affect the vigor of your plants. Occasionally dig up a small tuber and check for any damage to the young potato. If you use clean new compost, you won’t have any major soil borne insect problems.
Give your potatoes a feed which has a high potash content. This substantially increases the potato yield. Avoid using feeds with a high nitrogen content because this encourages the growth of excess leaves at the expense of the potato crop. Potato blight can rear it’s ugly head during humid periods. Therefore, it’s better to avoid recycling compost. Also, buy certified seed rather than planting old potatoes to help prevent blight infection and other diseases. As already mentioned, grow early varietiesor look for blight resistant seed potatoes such as Sarpo Mira, Setanta or Orla. Please check with your local seed supplier.
Harvesting your bag potatoes
You will know they are ready to harvest when the flowers start to bloom for a couple of weeks. You can test to see if they are at the size you want by gently removing some of the topsoil and having a look. Leave them to grow to maturity and pick when ready.
You have to harvest early potato varieties as they are needed because they don’t store very well. You can leave maincrop varieties in the bags for longer periods as long as the bags are in well ventilated areas.
Once you harvest, store the potatoes in hessian bags or in sand in a cool environment. Avoid storing potatoes in polythene bags because they’ll ‘sweat’ and rot. Also, check your harvested potatoes occasionally for signs of rot, and if you find any, remove them so that they don’t infect the other potatoes.