Harvesting and storing home garden vegetables

UNIVERSITY OF MINNESOTA EXTENSION - www.extension.umn.edu

One of the joys of summer is homegrown sweet corn, picked right outside your back door and plopped straight into a pot of boiling water or onto the grill. The advantage of having a home garden is that you can pick and savor your vegetables when they are at their optimal flavor. But how can you tell when to harvest your vegetables? How should you store zucchini if they all reach optimal size at the same time? What are the best conditions to store your homegrown vegetables?

Harvest

When harvesting vegetables, be careful not to break, nick or bruise them. The less you handle your vegetables, the longer they will last in storage. Harvest only vegetables of high quality. Rotting produce does not keep for very long, and can spread disease to other stored vegetables.

Storage

Different vegetables need different storage conditions. Temperature and humidity are the main storage factors to consider. There are three combinations for long-term storage:

1. cool and dry (50-60°F and 60% relative humidity),
2. cold and dry (32-40°F and 65% relative humidity), and
3. cold and moist (32-40°F and 95% relative humidity).

For cold conditions, 32°F is the ideal temperature. This temperature is not easy to attain in most homes. Expect shortened shelf-lives for your vegetables as storage conditions deviate from the ideal temperature. This shortening of their life span can be up to 25 percent for every 10°F increase in temperature.

Basements are generally cool and dry. If storing vegetables in basements, provide your vegetables with some ventilation. Harvested vegetables are not dead, but they still "breathe" and require oxygen to maintain their high quality. Protect them from rodents.

Home refrigerators are generally cold and dry (40°F and 50-60% relative humidity). This is fine for long-term storage of garlic and onions, but not much else. Putting vegetables in perforated plastic bags in the refrigerator will provide cold and moist conditions, but only for a moderate amount of time. Unperforated plastic bags often create too much humidity, which leads to condensation and growth of mold or bacteria.

Root cellars provide cold and moist conditions. As with basements, provide ventilation and protection from rodents when storing vegetables in cellars. You can use materials such as straw, hay or wood shavings for insulation. If using such insulation, make sure that it is clean and not contaminated with pesticides.

Some vegetables, such as cucumbers, peppers and tomatoes, require cool (55°F) and moist storage. These conditions are difficult to maintain in a typical home. Expect to keep vegetables requiring cool and moist storage conditions for only a short period.

Harvest and storage information for commonly-grown vegetables

Expected shelf-life times are only estimates.

 Asparagus

• Harvest the third year after planting when spears are six to nine inches long.
• Store in cold and moist conditions. Keep upright during storage.
• The expected shelf-life is two weeks.

 Basil

• Harvest when leaves are still tender.
• Store at room temperature.
• Keep stems in water. Basil will discolor if kept in the refrigerator for 10 days.
• The expected shelf-life is five days.

 Beans, snap

• Harvest two to three weeks after bloom when the seeds are still immature.
• Store in cold and moist conditions.
• Beans will develop pitting if stored below 40°F.
• The expected shelf-life is one week.

 Beets

• Harvest when they are 1 ¼ to 3 inches in diameter.
• Store in cold and moist conditions without their tops.
• The expected shelf-life is five months.

 Broccoli

• Harvest while the flower buds are still tight and green.
• Store in cold and moist conditions.
• The expected shelf-life is two weeks.

 Brussels sprouts

• Harvest when the heads are one inch in diameter.
• Store in cold and moist conditions.
• The expected shelf-life is one month.

 Cabbage

• Harvest when the heads are compact and firm.
• Store in cold and moist conditions.
• The expected shelf-life is five months.

 Carrots

• Harvest when the tops are one inch in diameter.
• Store in cold and moist conditions without their tops.
• The expected shelf-life is eight months.

 Cauliflower

• Harvest while they are still white and before the curds are “ricey.”
• Store in cold and moist conditions.
• The expected shelf-life is three weeks.

 Corn, sweet

• Harvest then the silks are dry and brown. The kernels should be milky when cut with a thumbnail.
• Store in cold and moist conditions.
• The expected shelf-life is five days.

 Cucumbers

• Harvest for slicing when the cucumbers are six inches long.
• Store in a cool spot (55°F) in the kitchen in perforated plastic bags. Storage in the refrigerator is also possible for a few days.
• Cucumbers develop pitting and water-soaked areas if chilled below 40°F.
• Do not store with apples or tomatoes.
• The expected shelf-life is one week.

 Eggplant

• Harvest before the fruit’s color dulls.
• Store in a cool spot (55°F) in the kitchen in perforated plastic bags. Storage in the refrigerator is also possible for a few days.
• Eggplant develops pitting, bronzing and pulp browning if stored for a long period below 50°F.
• The expected shelf-life is one week.

 Kohlrabi

• Harvest when two to three inches in diameter.
• Store in cold and moist conditions without their tops.
• The expected shelf-life is two months.

Lettuce

• Harvest while the leaves are tender.
• Store in cold and moist conditions.
• The expected shelf-life is one week.

Muskmelons (cantaloupe)

• Harvest when the fruit slips off the vine easily, the fruit is firm and the netting is even.
• Store in cold and moist conditions.
• Muskmelons develop pitting and surface decay with slight freezing.
• The expected shelf-life is one week.

Onions

• Harvest when the necks are tight and the scales are dry.
• Store in cold and dry conditions.
• Cure at room temperature for two to four weeks before storage.
• Do not freeze.
• The expected shelf-life is four months.

Parsnips

• Harvest when the roots reach their desired size and/or after a light frost.
• Store in cold and moist conditions.
• Do not wax or allow the roots to freeze.
• Parsnip sweetens after two weeks of storage at 32°F.
• The expected shelf-life is four months.

 Peas

• Harvest when the pods are still tender.
• Store in cold and moist conditions.
• The expected shelf-life is one week.

 Peppers

• Harvest when the fruits reach desired size or color.
• Store in a cool spot (55°F) in the kitchen in perforated plastic bags. Storage in the refrigerator is also possible for a few days.
• Peppers develop pitting below 45°F.
• The expected shelf-life is two weeks.

 Potatoes

• Harvest when the vine dies back.
• Store in cold and moist conditions. Keep away from light.
• Cure at 50-60°F for 14 days before storage.
• Potatoes will sweeten below 38°F.
• The expected shelf-life is six months.

 Pumpkins

• Harvest when their shells harden and before a frost.
• Store in cool and dry conditions.
• Pumpkins are very sensitive to temperatures below 45°F.
• The expected shelf-life is two months.

Radishes

• Harvest when the roots are up to 1 ¼ inches in diameter.
• Store in cold and moist conditions without their tops.
• The expected shelf-life is one month.

Rutabagas

• Harvest when the roots reach a desired size.
• Store in cold and moist conditions.
• Do not wax.
• The expected shelf-life is four months.

 Spinach

• Harvest while the leaves are still tender.
• Store in cold and moist conditions.
• The expected shelf-life is 10 days.

Squash, summer

• Harvest when the fruit is four to six inches long.
• Store in a cool spot (55°F) in the kitchen in perforated plastic bags.
• Do not store in the refrigerator for more than four days.
• The expected shelf-life is one week.

Squash, winter

• Harvest when the shells are hard and before a frost.
• Store in cool and dry conditions.
• Curing is unnecessary. Do not cure the Table Queen variety.
• The expected shelf-life is two to six months, depending on variety.

Tomatoes, red

• Harvest when the color is uniformly pink or red.
• Store in a cool spot (55°F) in the kitchen in perforated plastic bags.
• Tomatoes lose color, firmness and flavor if stored below 40°F.
• Do not refrigerate.
• The expected shelf-life is five days.

 Turnips

• Harvest when the roots reach a desired size.
• Store in cold and moist conditions.
• You can wax turnips.
• The expected shelf-life is four months.

 Watermelons

• Harvest when the underside turns yellow or the fruit produces a dull sound when slapped.
• Store in a cool spot (55°F) in the kitchen in perforated plastic bags. Storage in the refrigerator is also possible for a few days.
• Watermelon will decay if stored below 50°F for more than a few days.
• The expected shelf-life is two weeks.