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Fruits & Vegetables

Potatoes

Potatoes thrive in cool, humid conditions. They are not well adapted to long, hot summers. Ground for them should be sunny, well-drained, and fertile. Work composted or well-rotted manure and or bone meal into soil prior to planting. Avoid fresh manure and lime as this encourages scab disease.

Prior to Planting

For planting, “seed” potatoes are used. These are not seeds, but are small-sized tubers selected for the purpose. Small ones may be planted whole, but it is more usual to cut bigger ones into chunky pieces containing two eyes per piece. Cutting should be done one or two days prior to planting so they can callous over; this reduces the chances of disease organisms invading the tuber. You may also wish to dust them with sulphur or some other fungicide.

Planting

Plant two weeks before the average date of the last killing frost in spring (early to mid May). Space seeds 1 foot apart in trenches that are 4 to 5 inches deep. Trenches may be spaced 1 to 1 1/2 feet apart. Loosely cover with a couple inches of soil; do not tamp the soil. When plants are 3 inches high, hill soil up to them to form ridge along each row. A second or third hilling will be needed as the tops lengthen. Never hill potatoes when the plants are in bloom. Lateral shoots that produce tubers could become damaged, lowering your yield.
**note: it is a good idea to rotate your potato crop (plant in a different area each year - rotate between 4 areas) as this helps to reduce the incidence of disease, insects and fungi.

Watering

Watering on a regular schedule will supply you with higher yields with fewer pest problems. During hot summer days, more water will be required. It is important that the plants receive adequate moisture when the potatoes are forming (approximately 6 to 10 weeks after planting).

When to harvest?

For early and mid to early varieties, harvest when needed for the table, beginning as soon as potatoes are big enough. If unsure of the size, you may want to pull away some of the soil by hand and remove some potatoes. This will slightly damage the plant, but it will continue to produce. For late varieties, wait until the tops have turned quite brown and shrivelled or when they have been killed by frost. Lift potatoes with a garden fork taking great care not to spear or otherwise damage them. Allow those intended for storage to lie on the ground in a shaded area for an hour or so to dry.

Storage

Once harvested place in a dark, frost-free place that is fairly humid. The ideal temperature should be around 45oF. Check potatoes every two weeks and remove decaying ones. Properly stored potatoes can keep for up to 8 months. Potatoes stored at room temperature are at their best for about only 10-14 days.

Space Saving Method

If space is limited, you can still have a crop in approximately 3 cubic feet. Old tires are used to grow in. Simply place the tire on a well-drained surface (gravel is best). Fill with soil and place 3 pieces of potato, spaced evenly. Cover as usual. When tops are high enough stack a second tire on and fill with soil. Repeat again for third tire. This method will give you a large yield of smaller, cleaner potatoes in a very small space.

Common Problems

Potato Scab

Crusty, scab-like lesions on skin. Plant scab resistant varieties e.g. Yukon Gold, Russet Burbank, Norland, Bintje. Avoid planting in soils where potatoes have been planted previously. Avoid alkaline soils (high in lime). Use only well rotted manure, not fresh.

Hollow Potatoes

They grow too fast, forming hollow centres. Soil has excessive nitrogen. Seeds are spaced too far apart. Decrease problem by using small whole seeds, maintaining uniform moisture levels, adequate but not excessive nitrogen and tighter spacing on planting.

High Potato Vines, Yet Few Potatoes

High nitrogen content in soil. Late variety might be delayed enough to prevent reasonable sizing prior to frost. Avoid fresh manure, use less fertilizer.

Wireworms

Plants are stunted and grow slowly. Tunnels wind through stems, roots and on the surface of the potato. Yellow to reddish-brown worms are found in the potato and soil. Infestations are most extensive in soil where grass or grassy weeds have grown during the last two seasons. Wireworms will feed for 2 to 6 years before maturing into beetles.
Controls -

  • Avoid planting in areas that were covered by clover, grass or grassy weeds
  • Cultivating the soil in spring prior to planting. Exposes the worms to predators as well as cutting them up.
  • Chemical controls have been shown to be ineffective.