Potatoes are one of the easiest and most prolific home garden vegetables.
The taste of freshly dug potatoes is a far cry from the starchy flavourless pulp that results from grocery store varieties bred for size and storage.
Potatoes are so easy to grow that it is almost impossible to fail with them. But people do it anyway.
They can rot in poorly drained soils or even worse, grow to size but come out of the ground looking like moon rocks, covered with pits and scabs.
There are a couple of DOs and a couple of DON’Ts that will guide you to assured success.
DON’T put lime on the potato patch. Veggie gardeners in southwestern B.C. do have acidic soil and most plants benefit from lime so we just splash it around like powdered sugar on waffles. Pick a waffle where the potatoes are going and leave it naked.
Potatoes don’t mind mildly acidic soil and they will get pitted skins in the presence of lime.
DON’T put fresh manure on the potato patch. In fact, don’t put fresh manure on the garden at all. Manure is a really useful thing to add to soil. It lightens clay soils and improves the moisture retention of sandy soils. It also contains viruses and other pathogens, some of which contribute to scabs on your potatoes. I prefer to compost “composted manure” for at least an extra year before using it.
DON’T plant this year’s potatoes in the same bed as last year’s potatoes. Pests, fungi and moulds build up year over year. Give your spuds an escape route.
Last year’s bean or pea patch should have a nice nitrogen base for potatoes. Plant them there.
DO wait until the last possible frost has passed before planting. If you have sandy soil, plant in mid- to late April, with clay soils mid-May.
DO add an organic source of nitrogen, potassium and phosphorus. Potatoes are heavy feeders. Three weeks before planting, spread about half an inch of finished, stable compost over the bed and work in with two litres of canola meal (or other complete organic fertilizer) per 100 square feet.
DO add 1/8 to 1/4 cup of bone meal to the hole when you plant your potatoes. Without calcium, potatoes don’t do much of anything.
DO sprout your potatoes in indirect light for a couple of weeks before planting them.
Be careful not to damage the sprouts and make sure they are facing up when you plant them.
Feel free to cut large seed potatoes in half, but make sure each piece has at least three sprouts.
Dig holes or a trench about a foot deep and place a seed potato every 18 inches. Cover the seed with about two inches of soil, mixing the soil with a little bit of old straw (I grow oats as a cover crop for this very purpose) or shredded leaves to keep the cover light and fluffy.
When the vines are about 12 inches high, gently pull soil up around the vines with a hoe, leaving about four to six inches of vine above the surface. Continue to hill the soil about once a month until the hot weather kicks in, sometime in July. Potatoes only grow above the seed, so each time you hill the soil you increase the productive zone of the plant.
Harvest new potatoes in July and your keepers in late August or early September, after the vines have turned brown. Don’t water for the last two weeks and pick a dry stretch of weather for harvesting.