HOW TO GROW A POTATO
There are many, many varieties of potatoes, each with its own claim to fame: early, late; yellow, purple; roasters, fingerlings but I’m keeping things simple and just calling a potato a potato for the purposes of this book.
Potatoes are so very easy to grow and they don’t need much soil to grow in. I’m sure I’m not the only one who’s found a couple of long forgotten spuds in the back of a cupboard, with their tangled white shoots looking like alien tendrils preparing to break out and snatch the family pet. These sprouted potatoes can be planted and they might well produce a few small potatoes. However, it’s much better to buy some seed potatoes at a garden centre or farm supply store.
You won’t need many. Each “eye” of a potato will produce its own mother plant, so one potato can be cut into several pieces, with care taken to ensure that each piece has at least one eye. It doesn’t hurt to let the cut skin dry out for a day or so. This is not essential but certainly helps to prevent rot and fungal attack. The potato plant is a vine and it can be encouraged to grow upwards rather than sprawl outwards. Vertical growth means a smaller footprint which in turn means more room for other plants. This is especially useful when space is limited.
Small Space Planting
To encourage vertical growth, potatoes are planted in an enclosed but open ended (top and bottom) structure. This can be as simple as a vertical cylinder of snow fencing, a barrel or a specially constructed box. Whatever the structure, it is not filled to the top with soil. A few inches at the base are all that is required to cover the cut up pieces of seed potato. Once the shoots appear above the surface of the soil they are surrounded with an organic mulch, usually straw or leaves and this process is repeated several times, thereby encouraging the vine, along with its fruit, to keep reaching upwards instead of sideways. This stacking technique will save a lot of space as the potatoes can be planted much closer together. However, this method only works well with strains that are of an indeterminate variety, that is, which grow on a vine that does not have a predetermined length. Most of the more common varieties of potato are determinate and will only produce one largish clump of potatoes. Only a few late season varieties will keep producing. Having said this it’s important to note that all potatoes like to be mulched at least once, as they tend to grow very close to the surface. Mulching prevents some of the crop from becoming “sunburnt”—read: green and toxic.
If space is not an issue and the seed potatoes are being planted the traditional in-ground way, each plant will require about 18 inches of elbow room to flourish. They will definitely produce better if they are mulched at least once. Along the shore where I live it was common practice, not so long ago, to grow a winter’s worth of potatoes in banks of eel grass (a dark colored sea grass that washes up every fall and that looks a lot like shredded paper). That practice is a good indicator of how little actual soil potatoes require. However, they prefer their soil to be slightly acidic. No lime is needed here as alkaline soil might encourage the growth of scab.
When to Plant
Potatoes are super easy to grow in that, once planted, they can be forgotten about, pretty much, until it’s time to dig them up. Probably the most crucial factor for success is timing. In those first heady days of warm spring sunshine, when my green thumb is itching and I’m thinking it’s probably time to plant potatoes, I’ve learned (the hard way) to wait a couple of weeks at least. Potatoes really do not like cold soil and it takes more than a couple of balmy days to warm the soil enough to suit potatoes. Even if they don’t simply rot and turn into nasty smelling slime, they’ll probably go into a non-productive sulk if the temperature of the soil is not to their liking. There’s nothing to be gained by planting too early.
It’s useful to remember that soil which may feel warm enough on top will be several degrees colder a couple of inches below the surface. A hand laid on the surface of the soil will tell a different story to a finger poked deep into the soil. It’s not unusual to discover ice crystals six to eight inches below the surface well into May, at least around here, and they don’t do a thing for warming up the soil!
Once established, each potato eye will produce a leafy plant which is a couple of feet high and similar in breadth. The plants produce pretty purple, blue, pink or white flowers with yellow centers. These will begin to die off after a week or so and eventually the plant itself will begin to wither and turn brown. By that time the days will be considerably shorter and cooler and a sense of fall will be creeping into the air.
When to Harvest
It’s best to harvest potatoes a couple of weeks before the first frost, leaving enough time to allow them to “cure” for a couple of days in the sun. It’s important not to leave potatoes exposed to daylight for long as this will cause them to turn green and poisonous. A short, gentle sun-bake will toughen up the skin a bit so the crop can be stored more successfully. After a day or so the excess soil will have dried and can be easily brushed off before the potatoes are layered in wood chips, or between sheets of newsprint in open weave containers such as plastic laundry baskets, and stored in a cool dark place. Again, potatoes should not be exposed to light for too long as they will turn green and become toxic due to a concentration of solanine, which is the potato’s natural defense against pests and fungus.
Harvesting potatoes on a warm fall day is a truly special experience, somewhat reminiscent of a treasure hunt, with potatoes tumbling out of the ground in exuberant excess. This is definitely an experience worth sharing and certainly enough to counter the weary reasoning against growing potatoes, which always revolves around the low cost and excess availability of potatoes in supermarkets.
This reasoning doesn’t touch on the alarming number of times commercially produced potatoes are sprayed (there is even a spray to kill the blossoms) in order to accelerate their growth and the fact that a potato is like a sponge, absorbing whatever is in the soil around it. I prefer just a little salt on my potatoes, thank you. And besides that, the pleasure of the “treasure hunt,” with some extra little hands along to “help,” does not have a price.