Growing potatoes seems to be one of the most popular topics among gardeners. There are many myths created about the proper way to grow potatoes. This article is meant to provide you with an outline of what conditions a potato needs to thrive and produce a large crop, a few steadfast rules and a few proven suggestions on how to plant your seed potatoes.
Potatoes will grow in almost any soil type but do grow better if the soil has pH range of 4.8 to 5.5 (neutral pH 7.0), a little on the acidic side. If your soil is closer to neutral or more basic, add oak leaves, sawdust or pine needles to compost or a bit of powdered soil acidifier, in the soil in your potato patch in order to make the soil a little more acidic. Also if you plan to grow potatoes in certain areas of your garden do not add lime or manure to the area of your garden that you plan to grow potatoes in this year and next year. Both manure and lime can raise the pH of your soil causing it to be less acidic.
Many gardeners think that a potato plant produces the new potatoes right off of the seed potato that you plant. In reality that seed potato actually sends up a shoot that becomes the green plant above ground and as that plant grows, it produces runners, and new potatoes develop on these runners below the new plant, but above where the seed potato was planted. The seed potato that you planted dissolves in the soil, as it provides food for the developing plant.
You can plant potatoes as soon as the soil in your garden has warmed up to fifteen degrees Celsius, even if the threat of frost is still some time away. Only hold off on planting potatoes early in the season if you have had unusually wet spring conditions and the soil is waterlogged. Let the soil dry out before planting so the seed potatoes won’t rot before developing into new plants.
A few days before you are going to be planting your seed potatoes, take them out of the box or bag they are stored in and look them over, as they should have developed many small shoots by now. The smaller potatoes, up to five centimetres in diameter, should be planted as is, regardless of how many shoots have developed. Larger seed potatoes can be cut into smaller pieces making sure each piece that you cut has a minimum of three eyes developing into shoots on each piece. Just use your best judgement here, and if you find that a larger potato is too hard to cut between the shoots then just leave it whole. Any potatoes that have eyes that haven’t swelled or developed shoots by now or have signs of rot, throw away, because they probably will not develop into a potato plant.
Once you have finished cutting your seed potatoes, lay them out on a tray or layer of newspaper in a dark, warm place for a few days to give the cut areas a chance to “seal off,” preventing rot from occurring and disease from entering the cut wounds when they are planted. Some gardeners swear by adding sulphur powder to their seed potatoes because it is a natural protector against disease. You can find sulphur in powder form at a feed store, garden supply store or some drugstores. A little goes a long way, so a small container is fine. The best way to apply the sulphur is to apply it right after the cuts are made while they are still damp, so the powder will stick. Put a few tablespoons of powder in a paper or plastic bag and then add a few seed potatoes at a time, shake gently (IMPORTANT: do not damage the new shoots) until coated in sulphur and then remove with a rubber gloved hand.
When you are ready to plant, you must provide deep holes or trenches fifteen to twenty centimetres deep. This provides an area for the new plant to form and produce new potatoes and as you gradually fill in the hole the soil stays loose and allows for more tuber shoot penetration and a larger yield of new potatoes. You can dig individual holes for each hill or rows of trenches (some gardeners have a tiller attachment for this) across your planting area.
Space your holes (or potatoes in the trench) thirty to forty centimetres apart if you want to produce high yield with large potatoes. If you want to produce smaller sized potatoes (potatoes called creamers in the grocery store) space the holes or seed potatoes about ten to fifteen centimetres apart. Try a combination of spacing to get both sizes. Once your hole or trench is dug, place one seed potato in the hole with the shoots facing up. It is important that the shoots face up, as this is the new plant forming. You only need one seed potato per hole, as long as it has a minimum of three developing shoots. Contrary to popular belief, planting more seed potatoes in each hole does not produce more potatoes. What it does produce are multiple plants that compete for space, water and nutrients in each hole, actually reducing your crop yield.
Once you have placed your seed potatoes in the ground, cover with five centimetres of soil. Continue covering the plants in each hole (or the trench) with approximately five centimetres of soil as the new plant emerges. Covering with soil will also protect the plants from frost early in the season. Once the plants have grown the full height of the trench or hole let them grow up to be about twenty centimetres tall and then hill a mound of soil all around the plant, almost covering it again. Let it grow another eight to twelve centimetres and then hill again with a hoe. Remember that all of this hilling is providing the environment for new potatoes to develop in. The larger the hills and the looser the soil, the better the crop will be.
One word of warning though: never hill potatoes that have started to bloom. Once a potato plant has started to bloom, the tender shoots that produce new potatoes are developing. Hoeing around the plants to form a hill could sever these tender shoots, killing all of your new potatoes and destroying all of your hard work.
As important as a good nutrient level in the soil, is a good moisture level. Potatoes need a steady supply of moisture in order to develop into good sound vegetables. If there are hot dry spells you will have to supplement the moisture level of the soil with watering. Good constant moisture levels, moist but not waterlogged soil, prevents the potatoes from developing hollow spots in their insides. Keep up the hard work until the blossoms die on the plants and then you can harvest your potatoes and enjoy the fruits of your labour.
