There seems to be a growing (!) use of planting sacks for Potatoes. I did hear one neighbour grumble that it was the most expensive pound of potatoes he had had, ever!
Although my first attempt was far more successful than it should have been, I know I didn’t do things quite as I should have. But I tried again, and was successful. So here is my photo guide of How to Plant Potatoes in Sacks
What You Will Need
If you choose to buy proper sacks it will cost more for the first year’s crop but with care the sacks will last a long time. Or you can go down the thrift route and use anything that’s big enough e.g. Pot, tub, container, inside-out compost bags (they look neater black side out), anything you can lay your hands on that can hold about 3 buckets of compost.
You will see from the photo that I have chitted my Potatoes. This simply means resting the seed potatoes in trays or egg cartons with the bit with the most “eyes” facing up so that they can start sprouting. Put the tray into the light, but not direct sunlight. The ‘sprouts’ should be firm, stubby, and coloured.
A problem I have come across is if you order your seed potatoes and they are supplied too early. Keeping them until you are ready to chit them can be difficult. Try to keep them cool and in the dark. Sometimes the seed potatoes just can’t wait to get going and you may find that they have sprouted. Don’t panic just ‘chit’ them as described and the shoots should firm up. They may be a bit long so handle them carefully. You don’t want to knock any of the shoots off!
How to Plant Your Potatoes
To keep the costs down, I have mixed some cheap Multi-purpose compost (I bought 4 x 50 litres bags at a bargain price at the local supermarket) with soil I had from rotting down some old turf. It had been stacked for over a year, so all the plant growth etc. had mixed with the soil, which, in theory, makes for good potting soil. I used one bag of compost to fill 6 bags for this project. If you have enough home-made compost you could use that instead.
Place some broken crocks or as I have done here, roof tiles, over the drainage holes in the base of the sack. This prevents them from clogging up with the compost mix.
Add about a bucketful of your compost mix to your sacks, to give them a layer of about 4 inches/100mm in the base. Place the potatoes with the sprouts pointing skywards on the compost. I have planted three tubers to each of my sacks. I noticed that when Monty Don trialled planting in sacks, one year, he said one-per-sack or if you preferred smaller potatoes, plant two. However, many Suppliers provide you with three tubers for each sack. Once you’ve made your decision about how many to plant, cover them with some more compost so that they are just tucked up (covered over) nicely.
Don’t forget to water the sacks. And do keep adding compost to the sack as the shoots get to being about 4-6 inches high. Keep adding more compost as the potato plants grow until the bag is about 3/4 full. Do water the sacks regularly, but avoid getting the leaves wet as this can cause a disease called Blight.
Write a label, plastic, wood, anything that can stay in the sack or as I did when I ran out of labels, write the variety on the sack itself with a Sharpie. You think you will remember which variety is planted in which sack but you won’t, trust me, (ahem) I know from experience!
Five little Potato sacks sitting in a row…
Whilst the home vegetable grower traditionally plants Potatoes for a Summer harvest, how about trying some for the Autumn/Winter? Maybe even new potatoes for your Christmas Dinner? By mid-Summer you can buy tubers for planting then and harvesting from October onwards. The tubers have been kept in cold storage and dormancy so chitting is not necessary. Planting in the Summer sunshine, in warm soil means they get going rapidly. Just remember to move the sacks into a sheltered spot or greenhouse before the frosty weather starts
This second planting means you could get two crops from you sacks, how’s that for value-for-money? The first lot of compost will be depleted of nutrients, so probably best to start again with fresh.