|we are about to plant a late crop of potatoes in our garden. What type of fertilizer do we need to use. We didn't fertilize before and we had bad results.|
|If your potato crop was a disappointment last year, it might have been due to climate and growing conditions rather than a lack of fertilizer. As a matter of fact, too much fertilizer can encourge too rapid growth, which can cause hollow centers and misshapen tubers.
For best results, follow these general guidelines:
Potatoes prefer an acid soil with a pH of around 5.5 to 6. Mix some compost into the soil before planting and go easy on the manure, which can encourage potato scab. Since too much nitrogen will promote foliage growth at the expense of tuber growth, stick to fertilizers such as phosphate rock and greensand to provide nutrients.
Plant seed potatoes about 12" apart in rows 2 1/2' apart. (If your seed potatoes are large--say, larger than an egg, you can cut them into pieces before planting. Just be sure each piece has 2 or 3 eyes. Allow the cut potatoes to dry overnight before planting.) I like to plant in trenches about 6" deep, covering the seed potatoes with about 2" of soil.
Hilling potatoes encourages production of more tubers. When the plants reach about 6" tall, mound soil or mulch around the base of the plants within 1/2" of the lower leaves. (You'll be filling in the trench, if you made one.) Repeat this process several times throughout the summer.
I usually plant my potatoes about 2 weeks before the last frost date, but don't worry about planting them late--you will still get a harvest this season.