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Cucumber

Cucumber is a tender, warm-season vegetable that produces well when given proper care and protection. The vines of standard varieties grow rapidly and require substantial space. Vertical training methods and new dwarf varieties now allow cucumbers to be grown for slicing, salads and pickling, even in small garden plots.

Recommended Varieties

Long Green Slicing

Burpless (hybrid - 62 days to harvest; the original sweet, long, Chinese-type hybrid; does well on a trellis)

Marketmore 76 (68 days; very uniform, dark green, straight fruit; multiple disease resistance)

Straight 8 (58 days; AAS winner; long-time favorite; excellent flavor; evenly dark green fruit)

Long Green Slicing (compact plant)

Bush Crop (55 days to harvest; delicious; 6-8 inch fruit on dwarf, bushy plants)

Fanfare (hybrid - 63 days; AAS winner; great taste; high yield; extended harvest; disease resistant)

Salad Bush (hybrid - 57 days; AAS winner; uniform 8 inch fruit on compact plants; tolerant to a wide variety of diseases

Pickling

Bush Pickle (48 days to harvest; compact plant; good for container growing)

Carolina (Hybrid - 49 days; straight, blocky fruits with white spines; medium-sized plant with good vigor; disease resistant)

When to Plant

Cucumbers are usually started by planting seeds directly in the garden. Plant after the danger of frost has passed, and the soil has warmed in the spring. Warm soil is necessary for germination of seeds and proper growth of plants. With ample soil moisture, cucumbers thrive in warm summer weather. A second planting for fall harvest may be made in mid- to late summer.

Cucumbers may be transplanted for extra-early yields. Sow two or three seeds in peat pots, peat pellets or other containers 3 to 4 weeks before the frost-free date. Thin to one plant per container. Plant transplants 1 to 2 feet apart in rows 5 to 6 feet apart when they have two to four true leaves. Do not allow transplants to get too large in containers or they will not transplant well. Like other vine crops, cucumbers do not transplant successfully when pulled as bare-root plants.

Spacing & Depth

Plant seeds 1/2 to 1 inch deep and thin the seedlings to one plant every 12 inches in the row or to three plants every 36 inches in the hill system. If you use transplants, plant them carefully in warm soil 12 inches apart in the row.

Care

Cucumber plants have shallow roots and require ample soil moisture at all stages of growth. When fruit begins setting and maturing, adequate moisture becomes especially critical. For best yields, incorporate compost or well-rotted manure before planting. Cucumbers respond to mulching with soil-warming plastic in early spring or organic materials in summer. Use of black plastic mulch warms the soil in the early season and can give significantly earlier yields, especially if combined with floating row covers.

Side-dress with nitrogen fertilizer when the plants begin to vine. Cucumber beetles should be controlled from the time that the young seedlings emerge from the soil.

In small gardens, the vines may be trained on a trellis or fence. When the long, burpless varieties are supported, the cucumbers hang free and develop straight fruits. Winds whipping the plants can make vertical training impractical. Wire cages also can be used for supporting the plants. Do not handle, harvest or work with the plants when they are wet.

Harvesting

Pick cucumbers at any stage of development before the seeds become hard. Cucumbers usually are eaten when immature. The best size depends upon the use and variety. They may be picked when they are no more than 2 inches long for pickles, 4 to 6 inches long for dills and 6 to 8 inches long for slicing varieties. A cucumber is of highest quality when it is uniformly green, firm and crisp. The large, burpless cucumbers should be 1 to 1 1/2 inches in diameter and up to 10 inches long. Some varieties can grow considerably larger. Do not allow cucumbers to turn yellow. Remove from the vine any missed fruits nearing ripeness so that the young fruits continue to develop. The cucumber fruit grows rapidly to harvest size and should be picked at least every other day.

Common Problems

Cucumber beetles — 1/4 inch long. Black and yellow spotted or striped beetles. Feed on foliage, flowers, stems or fruit. Fly from one plant to another.

Crops attacked - Cucumber, muskmelon, pumpkin, squash (summer and winter), watermelon.

Symptoms of damage - Holes in foliage; chewed flowers; scarred stems and fruit surfaces. Spotted and striped cucumber beetles attack seedlings as they emerge from the soil. The beetle may appear in large numbers and can quickly stunt or kill the small plants. Beetles may carry bacterial wilt disease that causes plants to wilt and die.

For more information on cucumber beetles, see our feature in the Bug Review.

Aphids — Watch for buildup of colonies of aphids on the undersides of the leaves.

For more information on aphids, see our feature in the Bug Review.

Bacterial Wilt - Plants are infected with the bacterial wilt disease by the attack of cucumber beetles. The disease organism overwinters inside the beetles' bodies. The beetles hibernate among the trash and weeds around the garden, emerging in time to feed on tender cucumber seedlings. Plants usually are infected with the disease-causing bacteria long before they show any symptoms. When the vines wilt and collapse (usually about the same time that the first cucumbers are half grown), it is too late to prevent the disease.

Questions & Answers

Q. Some of my small cucumbers are badly misshapen. Will they develop into normal cucumbers?

A. No. They should be removed from the vines. Misshapen cucumbers may result from poor pollination or low fertility. Side-dressing with a complete fertilizer may help later cucumbers to develop normally.

Q. Why do some of my plants suddenly wilt and die? Dead or dying plants are scattered all over my cucumber patch. One plant in a hill may be healthy, while another dies.

A. These are typical symptoms of the bacterial wilt disease. This disease is spread by cucumber beetles early in the season. The beetles must be controlled immediately when the plants are small.

Q. Is there really a "burpless" cucumber?

A. Yes. Burpless cucumbers are no longer considered novelties and are offered in most garden catalogs. They are mild, sweet and crisp when fresh. The skin is tender and free of bitterness, although many people peel it off. Most varieties are long (10 to 12 inches) and curved, unless grown on a trellis. These varieties are better eaten fresh, using conventional varieties for most picklng uses.

Q. What cucumber variety should I buy for gherkins?

A. Buy the West Indian gherkin. It is a close relative of the garden cucumber used for pickling. The fruits are generally oval, 1 to 3 inches long and more spiny than cucumbers. They are also called "burr cucumbers" but are usually listed in catalogs as West Indian gherkin. They are grown in the same way as cucumbers. Small-fruited, prickly varieties of cucumber are sometimes sold as "gherkins." If small, tender cucumbers are what you want to pickle and call "gherkins," then these misnamed cucumber varieties serve the purpose well.

Q. Why do my cucumbers fail to set fruit and yield properly?

A. The first yellow flowers appearing on the plants are male flowers that provide pollen. These flowers normally drop off after blooming. The small cucumber is evident at the base of the female flower (even before it opens) and should develop into an edible fruit if properly pollinated. Anything that interferes with pollination of the female flowers reduces fruit set and yield, including cold temperatures and rainy weather that hamper bee activity or improper use of insecticides that kill bees.

Q. What are gynoecious hybrids?

A. Gynoecious ("female-flowering") hybrids are special hybrids of slicing and pickling cucumbers that are advertised in many garden catalogs. Because they have all female flowers, they may be earlier and higher yielding than other varieties. Usually, the seed company mixes in a small proportion of seed of a standard cucumber as a pollinator.

Q. How far away from melons should I plant my cucumbers? I am concerned about cross pollination.

A. Contrary to popular opinion, cucumbers do not cross-pollinate with muskmelons or watermelons and cause them to become bitter, tasteless or off-flavor. Because cucumbers and melons require considerable space in the garden, however, plant the rows far enough apart for proper vine growth without overlapping.

Q. What causes my cucumber plants to be stunted? The leaves are a mottled yellow, and the fruits are blotchy and taste bitter.

A. This condition is caused by the cucumber mosaic virus. Grow mosaic-resistant varieties.

Q. What causes the white mold growth on the upper surfaces of my cucumber leaves?

A. This condition is caused by powdery mildew, a fungal disease that is most severe during late summer and fall plantings. Grow resistant varieties.

Selection & Storage

There are two types of cucumbers common to the home gardener - pickling cucumbers and slicing cucumbers. The phrase "cool as a cucumber" is an apt one. Growing in a field on a hot summer day, the interior flesh is 20 degrees cooler than the outside air temperature.

Harvest cucumbers early in the morning (before have been heated by the afternoon sun) and refrigerate immediately. Store for up to 3 days in the refrigerator in loose or perforated plastic bags. Supermarket cucumbers are covered with an edible wax to protect them from moisture loss. The wax gives them an unnatural sheen. Fresh cucumbers are dull green in color.

Pickling cucumbers — Pickling cucumbers should be picked every day, since they can quickly grow too large for use. Do not leave over-mature, yellow cucumbers on the vine. If a single cucumber is left on the vine, the vine will stop producing altogether.

Slicing cucumbers — Slicing cucumbers should be harvested as needed. But there is no practical use for baseball bat size cucumbers. They are tough and the seeds are woody. Harvest when they are 8 inches long or smaller. As with pickling cucumbers, remove the over mature ones as soon as you see them or they will halt the growth of new cucumbers.

Nutritional Value & Health Benefits

Cucumbers add a crisp snap to salads and sandwiches, however they are not a very good source of nutrients. The most abundant nutrient in cucumbers is water. A small amount of beta carotene is found in the green peel, but once peeled the level drops to nearly zero.

Nutrition Facts (6 large or 8 small raw cucumber slices with peel)

Calories 5
Protein trace
Dietary fiber 1 gram
Carbohydrates 1 gram
Calcium 7 mg
Vitamin A 70 IU
Vitamin C 3 mg
Iron trace

Preparation & Serving

Cucumbers are often soaked in salt water to remove some of the naturally high water content. Cucumbers will otherwise give up water and dilute the salad dressing. Unpeeled cucumbers are higher in nutritional value as fiber and vitamin A are lost by peeling.

Home Preservation

Aside from pickling, there is no practical way to preserve cucumbers. There are many ways to make a pickle. They can be fermented or quick packed in a vinegar solution and processed in a boiling water bath and kept on the shelf for up to a year. There is no great challenge to making pickles. Pickles can be made by the quart or by the five-gallon crock. For those who do not know how to can, pickles can be made in the refrigerator or in the freezer. Pickling cucumbers are best to use because the skin is less bitter than slicing cucumbers and they have smaller and fewer seeds. However, you can successful substitute slicing cucumbers.

Below are two ways to make pickles without canning.

Refrigerator Dill Chips

Pickled cucumbers add spice and texture to sandwiches and meals. For highest quality pickles, use cucumbers that are no more the 24 hours from the vine. Use "pure" or pickling salt in this recipe. Table salt contains additives that make a cloudy brine and off color pickles.

  • 2 to 2-1/2 cups sliced cucumbers, about 1/4 inch thick
  • 2-1/2 teaspoons pickling salt
  • 2 springs fresh dill, about 6 inches long or 1 tablespoon dry dill seed or 1 head of fresh dill
  • 2 cloves garlic
  • 1/2 cup white distilled vinegar
  • 1/2 cup water

Prepare the jar, lid and screwband. Wash them in hot soapy water, rinse well and drain. Combine the sliced cucumbers and 1-1/2 teaspoons of the pickling salt. Toss well. Cover with cold water and let stand for 2 to 3 hours. Drain.

In a clean, hot, 1 pint jar, put the dill, garlic, and remaining 1 teaspoon pickling salt. Add the cucumbers slices leaving 1/2 inch head space. Push slices down and firmly pack. Combine water and vinegar and bring to a boil. Pour hot vinegar solution over cucumbers.

Use a plastic knife or spatula to release air bubbles. Insert knife down the side of the jar and gently push cucumber slices toward the center so that the vinegar solution gets between the slices. Pour on more hot vinegar solution if necessary. Leave 1/2 inch headspace (the space between the rim of the jar and its contents). Wipe the rim. Put the lid and screwband in place. Refrigerate for six weeks before eating.

Nontraditional Sweet Freezer Pickles

This is not your typical pickle recipe. No special equipment or ingredients are needed. This recipe produces a crisp, sweet pickle that goes well in salads, on sandwiches or as a side. The secret to the crisp texture is the sugar, so do not reduce the sugar in the recipe. This recipe works well with slicing, pickling, seedless or hothouse cucumbers.

  • 2 quarts cucumbers, peeled and thinly sliced (use any variety of cucumber)
  • 1 medium onion, sliced thinly
  • 1 tablespoon salt (table salt, canning salt or kosher salt can be used)
  • 1-1/2 cups sugar
  • 1/2 cup white distilled vinegar

Mix cucumbers, onions and salt in a large bowl and cover with plastic wrap. Set the bowl on the counter for 2 hours. Pour into a colander and drain water from cucumber mixture. Combine sugar and vinegar. Stir well and pour over cucumbers. Pack into freezer containers or zip-closure bags. Freeze immediately. Pickles are ready to eat in 3 or 4 days. They will keep in the freezer for up to one year.

Recipes

Cucumber Yogurt Salad Dressing

This is a delicious, heart healthy, low calorie salad dressing which can be used as a dip for steamed or raw vegetables or as a topping for baked potatoes or steamed carrots. Store in a covered container in the refrigerator for up to two weeks.

  • 1 medium cucumber, peeled, seeded and coarsely chopped (about 2/3 cup)
  • 2/3 cup plain, nonfat yogurt
  • 2 tablespoons minced red onion
  • 1 tablespoon toasted sesame oil or vegetable oil
  • 2 teaspoons rice vinegar or white vinegar
  • 1/4 teaspoon salt (optional)
  • 2 teaspoon chopped fresh dill or 1/2 teaspoon dried dill

Combine all ingredients in a blender or food processor and puree until creamy and smooth. Chill for about 2 hours before serving. Makes 1-1/2 cups.

Thai Cucumber Salad

  • 1/4 cup sugar
  • 1 teaspoon salt
  • 1/2 cup rice vinegar
  • 4 pickling or slicing cucumbers, sliced lengthwise, seeded and thinly sliced
  • 1 shallot, thinly sliced
  • 10 whole cilanto leaves
  • 1/4 cup red pepper, julienne (about 1 inch long)

Combine the sugar, vinegar and salt and heat in a small sauce pan until sugar has dissolved (about 5 minutes) do not boil. Set saucepan in cold water to cool the vinegar mixture. When cool, pour over cucumbers and garnish with red peppers. Serves four.