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VEGETABLE GARDEN: SELECTED VEGETABLE CROPS [continued]

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  MG Manual Reference
Ch. 10, pp. 114 - 116

[Selected Crops: intro | asparagus | beans | broccoli | brussels sprouts | cabbage | cauliflower | sweet corn | cucumbers | eggplant | lettuce | melons | onions | peppers | potatoes | squash | tomatoes | herbs | herb use ]

Potatoes
POTATOES Top

ENVIRONMENTAL PREFERENCES
Light: Sunny.
Soil: Well-drained with moderate organic matter.
Fertility: Medium-rich
pH: 4.8 to 6.5
Temp: Cool (55 to 65° F).
Moisture: Uniform moisture, especially while tubers are developing.
CULTURE Top
Planting: Plant 1 - 1/2 to 2-ounce seed pieces with at least one good eye in early spring.
Spacing: 10 to 12 inches by 24 to 36 inches.
Fertilizer Needs: Medium-heavy feeder. Add high phosphorus fertilizer before planting, using 1 tablespoon 10-20-0 per 10-foot row. Sidedress about 6 weeks after planting when tubers begin farming, using 5 tablespoons 33-0-0 per 10-foot row.
CULTURAL PRACTICES Top

Both white-skinned and red-skinned potatoes can be grown as an early crop for new potatoes and as a late crop for storage. Choose an early maturing variety and a medium- to-late maturing variety. Plant potatoes early from January 15 to April 20 depending on your location. Hard frosts and freezes may set back growth. Potatoes prefer cool springs and moisture throughout the growing season. Avoid a garden site in a turned-under lawn as grub worms may damage developing tubers unless soil insecticides are used.
A soil pH of 6.0 to 6.5 is most desirable; however, scab disease will be less when the pH is between 5.0 to 5.2. In addition to the base application of fertilizer, add about one-fourth pound of 10-20-10 for each 75 foot row. Work this into the furrow and mix with the soil before planting.
Purchase certified seed stock that has been inspected for diseases that lower yields. Saving your own seed potatoes is generally not worthwhile because viruses and diseases often show up the next year. Seed potatoes should be firm and unsprouted. Wilted and sprouted potatoes usually have lost vigor from being too warm in storage. Seed pieces for planting should be cut to about 1 - 1/2 to 2 ounces or into 1 - 1/2 inch cubes. Potatoes about six ounces in size will cut into four pieces nicely. Each seed piece should have at least one good bud or eye. Plant potatoes in furrows cut-side down, three to five inches deep. Later crops should be planted five to six inches deep.
Pull a ridge of soil over each row when planting. Drag a board or hoe across the ridges just before the sprouts break through to eliminate weeds. Later cultivation should be shallow and far enough from the rows to make certain that no roots are damaged.
When the tops have grown too large to allow cultivation, a finishing cultivation, sometimes called laying-by or hilling up is given. Laying-by throws soil over the potatoes to prevent exposure of the potatoes to sun which can cause greening or scalding. Green portions on potatoes taste bitter and contain an alkaloid. Cut off and discard green areas before using.
The release of the new true seed potatoes is an interesting development. The major advantage of growing potatoes from seed is the decreased chance of disease. For the home garden, growing from seed pieces is generally less time consuming and will give better yields. With time, true seed potatoes may be bred for higher yields; but at present, good quality stock potatoes yield the best crop.
COMMON PROBLEMSTop
Diseases: Early blight, scab, blackleg, soft rot, rhizoctonia, ring rot, tuber rots, virus complex, fusarium, verticillium, bacterial wilts.
Insects: Colorado potato beetles, flea beetles, leafhoppers, white grub, cutworm, psyllids, aphids.
Cultural: Green skin from sun exposure; hollow heart from alternating wet and dry conditions.
HARVESTING AND STORAGE Top
Days to Maturity: 100 to 120 days.
Harvest: Dig early potatoes when tubers are large enough to eat. Harvest potatoes for storage 2 weeks after the vines die down or just after the first light frost nips the vines, before heavy freezing. Avoid skinning tubers when digging and avoid long exposure to light..
Approximate yields: 6 to 15 pounds per 10-foot row.
Amount to Raise: 75 to 100 pounds per person (about 15 pounds of seed potatoes).
Storage: Medium-cool (40 to 50° F), moist (90% relative humidity) conditions for 6 to 8 months. Sprouting is a problem at higher temperatures.
Preservation: Medium-cool, moist conditions.

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