Best fertilizer for squash

The Best Fertilizers for Squash Plants

Squash plants of all varieties–from patty pans, zucchini and crookneck to acorn, butternut and spaghetti–all benefit from fertilizers and organic soil amendments. Well fed and supported squash plants will develop healthy fruit more quickly. Synthetic and organic fertilizers can be used on their own or in tandem support healthy growth and bountiful harvests.

Complete Synthetic Fertilizer

Apply a complete garden fertilizer with a guaranteed analysis of something like 10-30-10. Stagger the feedings throughout the growing season but not exceeding three pounds of fertilizer per 100 square feet in one year. Apply half of the fertilizer to the soil during planting in a trough offset from the seeds by three inches. Make the next application one month later.

Organic Soil Fertilizer Amendments

Fruits like squash respond well to organic amendments to enrich the soil both at planting time and as topdressing or mulch. Blend in a few pounds each of well-aged livestock manure and compost to the bed scratching into the soil surface and watering in well to leach the nutrients into the soil.

Late-Season Nitrogen Boosting

A high-nitrogen organic fertilizer formula such as 13-12-2 guano blend can be fed to the soil around your squash plants at the onset of harvest when the squash are ripening. This will “supercharge” the plants to remain vigorous and keep producing squash into the next season.

Care Of Summer Squash

Caring For Summer Squash

Improve The Harvest Trick

Early summer squash are produced from unpollinated female flowers. You want to get the male flowers to start. Here is the trick = Pick some of the first squash just after they begin to form; not all but some. This encourages male flowers to form and they will begin to pollinate the female flowers and definitely increase your plant’s production compared to if you did not use this technique. Harvest your summer squash before it gets much bigger than 8 inches even if you have more than you can eat. When you let some squash grow to be baseball bats you are slowing down the productive output of the plant.

Ensure Squash Plants Stay Healthy

While proper fertilizing and watering is important to the success of the squash harvest, there are some additional steps you can take that will make an enormous difference in the health of your squash plants. In the first week of every month you should spray your plants with Thrive and Plant Growth Activator. These two products will add beneficial microbes to the leaves of the plant and help fight disease as well as insure that the plant grows to its maximum capability.

Disease Prevention For Summer Squash

Summer squash is vulnerable to several fungal diseases such as powdery mildew. Now you can prevent the liklihood of having any disease problems by using a new organic biological fungicide called “Actinovate”. When you plant your summer squash seedlings you spray some actinovate on the roots. Then two weeks later you spray the leaves with Actinovate. Then spray Actinovate monthly through the growing season. You should not have any disease problems.

Fertilizing Summer Squash
While summer squash is considered a heavy feeder it requires low nitrogen and fairly high potassium and phosphorous for good fruit development.

At Planting – Add an organic granular fertilizer at a rate of 2 to 3 tablespoons per hill of three plants prior to planting.

When plants are 6 to 8 inches tall – add another tablespoon of fertilizer.

When blossoms appear – add another tablesoon of fertilizer.

Do not over fertilize with nitrogen as this encourages vine growth and retards fruiting.

Fioliar Spray Monthly – Summer squash will like a foliar spray of organic fish emulsion once a month through the season.
Watering Summer Squash
Summer squash is deeply rooted, so water slowly with 1 inch of water per week. Allow it to completely soak the soil 6-8 inches deep. Water in the morning or early afternoon so the foliage dries by evening. This helps prevent the spread of leaf diseases. Decrease watering later in the season to encourage fruit to mature. At this time, the root systems will be more extensive and able to withstand drier conditions.

Mulching Summer Squash

As soon as the plants are four or five inches tall apply 2 to 3 inches of organic mulch around each plant.

Harvesting Summer Squash

Summer squash is harvested and eaten in the immature stages when the rind is still very soft; at 6 to 8 inches long. When harvesting squash, leave a short piece of the stem attached to the fruit. It is best to cut the squash from the vine. Zucchini and crooknecks should be 6 to 8 inches long and 3 inches in diameter. Scalloped or patty pan squash are harvested when grayish or greenish white but before they turn ivory. Store summer squash in the refrigerator in a plastic bag; lasts 5 to 10 days. Summer squash cooked and run throught a blender can be frozen for soups and stews over the winter.

Month to Month Care for Summer Squash

Month of April You can start squash indoors about two weeks before last frost. You won’t be putting the seedlings out for two or three weeks after last frost. We offer a broad range of seed starting equipment and supplies in Yardener’s Tool Shed;

Month of May Squashes are warm season plants and do not do well until the soil and air temperatures are above 60 degrees F. Apply some slow release granular fertilizer to the soil as you prepare to plant squash.

Squash are normally planted in groups (called “hills”). Plant four seeds per hill and later thin to the best two plants per hill. Cover seed with one inch of soil. Space summer squash hills 3 to 4 feet apart

When the first blooms appear, apply a tablespoon of slow release granular fertilizer to each hill and water it in.

Summer squash is harvested and eaten in the immature stages when the rind is still very soft. When harvesting squash, leave a short piece of the stem attached to the fruit. It is best to cut the squash from the vine. Zucchini and crooknecks should be 6 to 8 inches long and 3 inches in diameter. Scalloped or patty pan squash are harvested when grayish or greenish white but before they turn ivory. Harvest spaghetti squash when the rind turns golden yellow. Banana squash is harvested when golden orange.

Month of June Remove old fruit to allow new fruit to develop. Check plants daily once they begin to bear. Under good growing conditions, the crop should be harvested every other day and sometimes every day.

Optional – After harvest begins, add a tablespoon of slow release fertilizer every two or three weeks to maintain vigorous growth and high productivity.

Month of July Summer squash is good when it is steamed but our favorite is to sautee round slices of the squash in butter and/or good olive oil spiced with some oregano either fresh or dried.

Month of August

Month of September

Month of October Summer squash plants will die with the first frost

All About Growing Summer Squash

Round and oval squash produce single-serving-sized fruits on compact, bushy plants suitable for large containers or intensive raised beds.

Tromboncino and zucchetta squash (C. moschata) produce large, curvaceous fruits with light green skins. Naturally resistant to insect pests, these rowdy, vining plants grow best on a trellis.

For more information about types of summer squash and our recommended varieties, see our Summer Squash at a Glance chart.

When to Plant Summer Squash

Sow summer squash seeds in prepared beds or hills in spring after all danger of frost has passed. You can also sow seeds indoors under fluorescent lights and then set out the seedlings when they’re 3 weeks old. In Zone 5 and warmer, you can sidestep early-season squash bugs by delaying the planting of seedlings until early summer. Stop planting summer squash 12 weeks before your average first fall frost date.

How to Plant Summer Squash

Choose a sunny site with fertile, well-drained soil with a pH between 6.0 and 6.5 for growing summer squash. Spots that were previously occupied by compost piles are especially desirable, or you can dig two heaping spadefuls of compost into each planting site. As you dig, loosen the soil to at least 12 inches deep and mix in a light application of a balanced organic fertilizer.

Plant summer squash seeds 8 inches apart, poking them into the soil 1 inch deep; water well. Thin seedlings to 3 feet apart. (If using transplants, set them out 3 feet apart.)

To prevent insect damage, install protective row covers over your squash as soon as you’re done planting. Read The No-Spray Way to Protect Plants for more tips about using row covers.

How to Grow Summer Squash: Boost Production

Summer squash produce male flowers on bare stems, while female flowers — usually preceded by the males — show a tiny squash at their base. You can improve yields in small plantings (fewer than five plants) by using a small paintbrush to spread pollen from male to female flowers, supplementing insect pollination.

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Harvesting and Storage

Summer squash blossoms are edible, and you can harvest fruits from baby-sized up until they toughen with age. Harvest at least twice a week, using a sharp knife to cut fruits (leave a small stub of stem attached). Promptly wash fruits in cool water and store in the refrigerator. For long-term storage, freeze or dry blanched pieces of summer squash.

Saving Seeds

With the help of bees and other pollinators that fly long distances, summer squash plants readily cross with one another, which doesn’t affect the current season’s crop but will change the genetic code carried in the seeds. Summer squash also cross with several varieties of winter squash that are of the same species (C. pepo), such as acorn or delicata squash. To grow summer squash for seed-saving purposes, set aside a hill where you can grow two plants of the same open-pollinated variety together. When the plants begin to bloom, cover them securely with a tent made of row cover or tulle to exclude pollinating insects. For a two-week period, hand-pollinate female flowers during the morning hours and promptly replace the tent. When three perfect fruits have set on each plant, remove covers and pinch off new flower buds until the seed-bearing fruits are fully ripe (with hard rinds and brown stems). Save and dry the largest seeds from the insides of each fruit. In good storage conditions, summer squash seeds will remain viable up to six years.

Pest and Disease Prevention

All types of summer squash face challenges from insects, including squash bugs, squash vine borers and cucumber beetles. To defend your plants from all three pests, cover them with row covers held aloft with stakes or hoops until the plants begin to bloom. Big, healthy plants will produce well despite pest challenges.

Powdery mildew is a late summer disease best prevented by growing resistant varieties, which often have the letters PM (for “powdery mildew-resistant”) after their variety name.

Growing Summer Squash Tips

Wait until the weather warms to grow summer squash, otherwise your plants will sulk in cold soil. Also, try growing summer squash around a compost pile located along the edge of your garden.

Choose hybrid varieties if you need a space-saving bush plant or a special form of disease resistance. Open-pollinated varieties often grow long vines that produce for an extended period of time and that may send out supplemental roots where the stems touch the soil.

Grow at least two different colors of summer squash each season for more colorful pizzas and prettier casseroles.

Cooking With Zucchini

Colorful and low in calories, summer squash offer quiet flavors that blend beautifully with fresh herbs, mushrooms and all sorts of cheeses. When freezing blanched squash, include chopped herbs and fresh greens or cherry tomatoes for added color and flavor. Grilling enhances the flavor of both fresh and frozen summer squash. A bumper crop will fill a freezer; drying blanched squash pieces will save storage space and give you high-quality veggies for winter soups and stews. Grate slightly overripe zucchini and use it in baked breads and muffins. All summer squash provide vitamins A and C along with dietary fiber. Many of the nutrients are most abundant in the squash skins.

Zucchini Plant Fertilizer: Tips On Feeding Zucchini Plants

Zucchini is one of the most popular summer squash varieties to grow in the vegetable garden, although they are technically a fruit, because they are easy to grow, prolific producers. One source states that the average plant produces between 3-9 pounds of fruit. My plants often exceed this number. To get the highest yield of fruit, you may question “should I fertilize zucchini.” The following article contains information on fertilizing zucchini plants and zucchini fertilizer requirements.

Should I Fertilize Zucchini?

As with any fruiting plant, zucchini can benefit from additional feedings. How much and when to apply zucchini plant fertilizer will depend on how well the soil was prepared prior to sowing or transplanting. For optimal production, zucchini should be started in rich, well-draining soil in an area of full sun. Summer squash are heavy feeders, but if you are lucky enough to have nutrient rich soil, you may not need any additional feeding of zucchini plants.

If you are interested in feeding zucchini plants organically, the time to start is prior to sowing seed or transplanting. First, select your site and dig up the soil. Dig in about 4 inches of well composted organic matter. Apply an additional 4-6 cups of all-purpose organic fertilizer per 100 square feet. If your compost or manure is high in soluble salts, you will need to wait 3-4 weeks before planting the zucchini to prevent salt injury.

Plant the seeds at a depth of one inch or transplant starter plants. Water the plants once a week to keep them moist, 1-2 inches per week depending upon weather conditions. Thereafter, apply organic zucchini plant fertilizer when plants just begin to bloom. You can use an all-purpose organic fertilizer or diluted fish emulsion when fertilizing zucchini plants at this time. Water in the fertilizer around the plants and allow to soak down into the root system.

Zucchini Fertilizer Requirements

An ideal zucchini plant fertilizer will certainly contain nitrogen. An all-purpose food like 10-10-10 is generally sufficient for zucchini plant needs. They contain plenty of nitrogen to facilitate healthy growth as well as necessary potassium and phosphorus to boost fruit production.

You may use a water soluble or granule fertilizer. If using a water soluble fertilizer, dilute it with water according to the manufacturer’s instructions. For granular fertilizers, scatter the granules around the plants at the rate of 1 ½ pounds per 100 square feet. Don’t let the granules touch the plants, as it may burn them. Water the granules in well.

As mentioned above, if you have rich soil, you may not need additional fertilizer, but for the rest of us, pre-preparing the bed with compost will limit the amount of additional feeding needed. Then when seedlings emerge, a light dose of general all-purpose fertilizer is ample and then again once the blossoms have appeared.

Homegrown Summer and Winter Squash

Circular 993 View PDF picture_as_pdf

Malgorzata Florkowska and Robert R. Westerfield, Horticulture
Technical Assistant: Adrianne Todd

  • Types
  • Soil Preparation
  • Culture
  • Fertilization
  • Harvesting, Storing, and Using
  • Problems
  • Insects
  • Disease

It is difficult to imagine summer without summer squash casserole or winter without winter squash soup. Both types of squash are very nutritious, have high fiber content and are high in vitamins A and C. Squash are not difficult to grow, so anyone who likes to garden can enjoy them first in the garden and then on the table.

Types

Summer squash grows on nonvining bushes. The three main types include: the yellow straight neck or crooked neck, the white scallop or patty pan, and the oblong, green, gray or gold zucchini.

Winter squash matures on the vine and is covered with a hard rind that permits winter storage. It is categorized according to its fruit size: small fruits (1 to 4 pounds) include acorn types, butternut types, and some true winter squash types; intermediate fruits (6 to 12 pounds) include banana squash, Cushow, Hubbard and some Sweet Meat varieties; large fruits (15 to 40 pounds) include Blue Hubbard, Boston Marrow and Jumbo Pink Banana varieties; jumbo fruits (50 to 100+ pounds) include Big Max and various Mammoth varieties.

Photo 1: Summer SquashPhoto 2: Winter Squash

Soil Preparation

All squash prefer organic, rich, well-drained soils. Organic matter will help increase uptake of water and nutrients. Adding compost or aged manure will give plants a good start. New garden sites should be amended with at least 4 to 5 inches of good organic matter and then tilled 8 to 10 inches into the native soil. The ideal soil should be slightly acidic (between a pH of 5.8 and 6.8) with a soil temperature range of 65 to 80 degrees Fahrenheit.

Culture

Plant summer squash in full sun after danger of frost is past. Plant four to six summer squash seeds in individual mounds 4 feet apart. After they have two leaves, thin to two to three plants per mound. Transplants can also be used. Make sure they have two to three mature leaves and a well-developed root system. Winter squash, because of its vining nature, needs more room. Allow 6 to 8 feet between mounds for plants to spread out. Winter squash requires warm soils and can be planted a few weeks after summer squash has been sowed.

After the plant seeds have germinated, apply some type of organic mulch. Grass clippings, straw and newspapers help to control weeds, conserve water and keep the fruits clean. Newly seeded gardens should be watered daily and lightly for the first week to ensure good germination. Established squash will require between 1 to 1½ inches of irrigation per week. Using drip irrigation or soaker hoses is the most efficient and healthy way to water plants. Moisture needs to penetrate 6 to 8 inches deep into the soil. Avoid wetting the foliage since doing so can lead to disease. Reduce watering once the fruits ripen to avoid fruit rot.

Squash has both male and female flowers and needs bees or other insects for pollination. If insect activity is low, female flowers are likely to drop. To avoid this, you can pollinate them yourself. Use a cotton swab to gather pollen from the male flower and distribute it onto the stigma in the center of the female flower. (Female flowers have a small ovary or swelling behind short-stemmed flowers. The male flowers are larger and have longer and thinner stems).

Fertilization

Fertilization of squash should begin at planting time. Get a soil test to find the most accurate fertilizer recommendations. In the absence of a soil test, apply 3 tablespoons of 5-10-15 fertilizer per planting mound at planting time. After the squash plants begin to flower and small fruits form, side-dress with additional fertilizer according to the soil test recommendations. Organic fertilizers can also be substituted to provide the nutritional needs of the plants. After fertilizing, be sure to water the plants thoroughly to help release the nutrients.

Harvesting, Storing, and Using

It takes 35 to 45 days for summer squash to mature. Summer squash should be harvested at a young stage for the best flavor. The optimal size is 4 to 6 inches long and 1½ inches in diameter. Generally, summer squash is harvested every other day. The sooner you begin harvesting, the sooner new squash is formed. Store summer squash at 45 to 55 degrees F for two to four days. Summer squash can be cooked, sautéed and used in casseroles and soups. Zucchini is often used shredded in breads, raw in salads or as a party dip. Summer squash does not freeze well.

Winter squash takes 80 to 120 days to mature. It is mature when fruits are fully colored, vines are starting to die back, and the rind is hard and resistant to scratches with fingernails. Matured fruits should be harvested with the stem attached and stored in a cool (50 to 55 degrees F), dark and dry location. Buttercup and banana squash store longer than butternut and acorn squash. Winter squash can be baked, steamed, simmered or mashed. Winter squash does freeze well (peel, cut into cubes and remove seeds; cook covered in water until soft; mash it and pack into containers leaving a 2-inch headspace; it will keep about a year).

Problems

Several serious insects, diseases and environmental factors attack summer and winter squash plants.

Insects

Aphids – Aphids are small insects found on new stems and on the underside of leaves. Leaves become yellow, crinkled and curled. The insects suck fluids from the plant, leaving a honey dew substance behind. To control, use insecticidal soaps or a strong stream of water to dislodge insects.

Squash Bugs – Squash bug adults are gray or brown and suck the sap from leaves, leaving them speckled before they wither and die. The bugs must be controlled while they are immature. To control, pick the bugs by hand or use insecticides.

Squash Vine Borer – Squash vine borer is a troublesome pest that begins as an adult that lays eggs in the lower stems of squash plants. Developing larvae tunnel and eat their way to the lower stems, causing plants to wilt and eventually die. Control is difficult, and prevention with a labeled insecticide is the key. If the insect is detected early, it can be carefully cut out with a sharp knife. Soil should then be mounded over the wound to encourage rooting.

Photo 3: Squash BugPhoto 4: Squash Vine Borer

Disease

Powdery Mildew – Powdery mildew is a white powdery substance that appears on older leaves. It eventually spreads to all parts of the plant. Use surface or underground watering methods to avoid wetting leaves, and/or plant resistant varieties.

Blossom-end rot – Blossom-end rot affects fruits. Fruits develop a black-rot on the end. Hot weather and lack of calcium, as well as a lack of moisture, increases susceptibility. To control, supply even moisture to the plant and supply lime as needed.

Photos by Malgorzata Florkowska, J. B. Robinson and Caley Anderson

Status and Revision History
Published on Nov 04, 2010
Published with Full Review on Nov 04, 2013
Published with Full Review on Aug 01, 2016

UConn Home & Garden Education Center

Cucurbits: Cucumbers and Squash

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Site and Soil
Cucurbits grow best in full sun sites with good air circulation and prefers soil that is moist, well drained, fertile and rich in organic matter. The soil’s pH should range from 5.5 to 6.8. Lime and fertilizer rates of application should be based on periodic soil tests. Natural fertilizers such as compost and manures, and slow-release commercial fertilizers along with limestone are effective when tilled into soil before planting time.
Varieties
There are many varieties of cucumbers and squash with great variation in shape, size, color, taste and texture. These plants are herbaceous (non-woody) annuals. Summer squashes are harvested as immature fruit, while winter squashes are harvested as mature fruit.
Image by Susan Pelton
Varieties of Cucurbits Suitable for Growing in Connecticut

Pickling cucumbers Alibi (res. to DM), Calypso (res. to DM, PM, angular leaf spot), County Fair (res. to bacterial wilt),Cross Country (resistant to angular leaf spot, DM), Little Leaf-19 (less attractive to Cucumber beetles, res. to DM), Score and Premier (both resistant to anthracnose)
Slicing cucumbers County Fair (res. to bacterial wilt), Dasher II (res. to DM. PM), Diva (res. to DM), General Lee (res. to DM), Marketmore 76 (res. to DM, PM)
Bush Scallop Peter Pan, White Ruffles, Sunburst
Spaghetti Orangetti, Vegetable Spaghetti,Tivoli (bush-type)
Summer Green Seneca Zucchini, Zucchini Elite, Cocozells Bush, Ambassador, Milano,
A and C Zucchini improved
Summer Yellow Early Prolific Straight neck, Seneca Prolific, Sundance,
Dixie, Goldrush, Multipik
Winter Waltham Butternut, Buttercup, Bush Buttercup, Gold Delicious,
Table Queen, Cream of the Crop, Blue Hubbard,
Golden Hubbard

Planting
Cucurbits are warm season crops that must be planted after all danger of frost is past and the soil has warmed.
They grow best at temperatures between 65ºF to 75ºF. Seeds germinate poorly at low soil temperatures, therefore, wait until the soil is 60ºF before planting. Plant seeds one inch deep and 12 inches apart in rows 40 inches apart, or plant several seeds in hills that are three feet apart. Thin plants in rows so they are two to three feet apart and thin plants in hills to two or three plants per hill. For vine-type squash, thin plants four to six feet apart.
Care
It is important to control the weeds through frequent shallow cultivation and/or with the use of mulches. A black plastic mulch stops all weed growth and can help in warming the soil. If using an organic mulch, wait until early July before laying it down to allow the ground to warm. Cultivate all the weeds before applying the mulch. Desirable materials include straw, saltmarsh hay or sawdust. Hay should be avoided because it may contain weed seeds.
Avoid using fresh lawn clippings or clippings from a lawn that was treated with an herbicide within the last six weeks.
Cucumbers and squash require a plentiful supply of water. Keep the soil evenly moist throughout the season. If it does not rain, an application of an inch of water per week will be enough.
Cucumber plants may be monoecious with male and female flowers on the same plant, gynoecious, with predominately female flowers (a few monoecious seeds may be included for pollination), or parthenocarpic which do not require pollination for fruit to set. Squash plants are monoecious, having male and female flowers on the same plant. Male blossoms appear first on a long stalk which often lifts the flower above the foliage. The female flowers are on a short stalk that resembles a small fruit. Squash requires cross-pollination, which is done mainly by bees or other insects.
Different varieties of squash will cross-pollinate, so do not save seed if different varieties are grown in the same area and flower at the same time. Cross-pollination will not affect the look or taste of this year’s fruit. It can affect the look and taste of the squash grown from the seed of the cross-pollinated plants.
Bush varieties are excellent choices for gardeners with small plots. Most of the summer squash are bush varieties.
Harvest
Harvest cucumbers and summer squash throughout the growing season. Pick summer squash with elongated fruits when they are less than three inches in diameter and up to eight inches long.
Scallop squashes are harvested at three to four inches in diameter. Winter squash should be picked when mature and fruits have hard rinds. If pumpkins and winter squash are picked prior to the seeds filling out then the plant will use starch reserves from the flesh to fill out the seeds resulting in a poorer flesh quality. Acorn and delicata squash along with pie pumpkins may be eaten immediately after harvest but butternut, Hubbard, and kabocha must be stored (cured) for 5-10 days at 80ºF with 80-85% relative humidity and night temperatures above 60ºF. This is not necessary for squash that will stored long-term.
Diseases, Insects, and Other pests
Cucurbit plants are subject to insect pests, mites and diseases. Their damage can be reduced by taking some preventive measures such as planting disease-free seed or transplants, selecting disease-resistant varieties, removing and destroying all diseased plants, controlling weeds properly, using crop rotation and keeping the garden and nearby area free of debris.
Blossom end rot of fruits may be caused by inadequate or uneven water supply and excessive nitrogen and certain other conditions which interfere with calcium nutrition in the fruit. Internal hardening, discoloration, or tissue collapse may be present even if there are no outward signs (image on right). Maintain a consistent water supply (1-2″ per week) and mulch around plant bases to help conserve moisture during hot, dry periods. Fertilizers should have low nitrogen, look for ratios of 4-12-4 or 5-20-5. Soil pH should be in the 6.0-6.5 range. There are no resistant varieties. Blossom end rot can also affect eggplant, peppers, tomatoes, and watermelon.
Diseases

Angular Leaf Spot
Pseudomonas syringae pv. lachrymans
Angular, water-soaked spots 1/8″ to 1/4″ across. Later spots dry up and drop out of leaf. Spread by moist, warm weather, overhead watering, and infected seed. Use a copper-based fungicide at the first signs of an infection.
Anthracnose
Colletotrichum orbiculare
Light brown spots near veins, 1/4″ to 1/2″ across on foliage. may fall out to give ‘shot-hole’ appearance.
On fruit, sunken spots, pink at first, later turning black.
Humid, rainy weather will promote this disease. Will survive on crop residue. Plant resistant varieties or use a fungicide labeled to control anthracnose as a preventive measure if it has been a problem in the past or at the first signs of an infection.
Bacterial Wilt Individual leaves wilt and turn dull green.
Gradually the entire plant wilts and dies.
Downy Mildew Yellow, angular spots within vein margins on
upper sides of leaves. Grayish-purple fungus
growth on underside of leaves. Fruit not affected. Plant resistant varieties.
Powdery Mildew
Podosphaera xanthii and Erysiphe cichoracaearum
Powdery gray-white growth on leaves and petioles. Premature defoliation often occurs. Fruit may be affected. Plant resistant varieties or use a fungicide labeled to control anthracnose as a preventive measure if it has been a problem in the past or at the first signs of an infection.

Insect Pests
Click on the highlighted links for control options

Cucumber Beetle Beetle 1/5″ long, yellow, three black strips down back.
Generally appear at the end of May.
Adults overwinter in debris in or near the garden.
Transmits wilt disease.
Melon Aphid Small, greenish-yellow to black insects found
on new growth and underside of leaf.
Spider Mites Very small, yellow or reddish mites.
Yellowish spots on foliage. Webs may be seen.
Squash Beetle A copper-colored 14-spotted lady beetle, the larvae feed
on the underside of the leaf, the adults on the top of the
leaf and the rind of the fruit.
Squash Bug Adults are flat, brown with orange on the abdomen,
about 3/4″ long. Young are gray with black legs.
Eggs are brownish and in patches on stems
and underside of leaves.
Squash Vine Borer White larvae of a clear-winged moth bore into stems
of pumpkins and squash. Overwinters as a pupa in
the soil, emerging in late June.

Please contact the UConn Home and Garden Education Center for control suggestions. Despite good cultural practices, pests and diseases at times may appear. Chemical control should be used only after all other methods have failed.
For pesticide information or other questions please call toll free: 877-486-6271.
All images ©UConn H & G
Revised by the UConn Home and Garden Education Center, 2016
Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, the Dean of the College, Cooperative Extension System, University of Connecticut, Storrs. The Connecticut Cooperative Extension System is an equal opportunity employer and program provider. To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, Room 326-W, Whitten Building, Stop Code 9410, 1400 Independence Avenue, SW, Washington, DC 20250-9410 or call (202) 720-5964.

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