Troubleshooting Pumpkin Plant Problems

Pumpkin vines, once planted, will grow un-cared for by man , all by themselves. They shant produce the bountiful fruits that a cared for pumpkin patch is capable of, but they will certainly help feed the insect and rodent populations.

To produce the bountiful harvest we desire, a pumpkin patch must be properly cared for. Part of this process is pest and disease prevention and treatment , and proper nutrients to help the plants in their development.

Rots and fungal disease are fairly common where ever pumpkins are grown.

Steps to Minimize Squash and Pumpkin Rot

  1. Maintain a fungicide- and insecticide-spray program during the growing season to minimize foliar diseases . Sulphur-based fungicides will control the most common surface-infecting fungal problems such as powdery mildew, black spot, apple scab and rust.
  2. Avoid Blossom End Rot of fruit by fertilizing and liming fields when needed.
  3. Harvest fruits when they are mature and the rind is hard, but before night temperatures are below 40oF and well before a frost .
  4. Do not harvest or handle wet fruit. Do not let harvested fruit get wet.
  5. Harvest fruit by cutting the peduncle (stem) with pruning shears to leave a 3- to 4-inch handle for pumpkins .
  6. Destroy pumpkins that are immature, injured, or have rot or blemishes. These pumpkins should not be harvested, stored and by all means don’t put them in the compost pile !.
  7. Do not pick up freshly harvested fruit by the peduncle, because it may separate from the fruit and provide easy access for rot organisms.
  8. Do not permit harvested or stored fruit to get wet.
  9. Washing is only necessary prior to consumption or cooking, but if washing is necessary, be sure the water is chlorinated (one part 5.25% liquid bleach to 999 parts water). Prepare fresh wash solution when the water becomes cloudy and chlorine cannot be detected. Dry thoroughly.
  10. For better keeping, some growers cure pumpkins for 10 to 20 days at 80 to 85oF with good ventilation (e.g. four air exchanges per day).
  11. Storage life of healthy pumpkins is typically 2 to 3 months without significant loss in quality.
  12. Mulching with organic matter such as straw or dry grass clippings helps control weeds, conserves moisture and keeps fruit from direct contact with the soil, where they could be infected by diseases

Common Diseases of Pumpkin and Squash

Black rot, is a phase of the disease called gummy stem blight that infects pumpkins. Caused by a fungus. Black rot is the most serious disease contracted during storage of squash, pumpkin, and gourds . Affected fruit may show black rot lesions in the field before harvest, collapse soon after harvest, or exhibit lesions some time later in storage.

Because infection originates in the field, control practices include the use of disease-free seed, a minimum 2-year rotation , and fungicide sprays as required. When powdery-mildew-resistant (PMR) varieties are released, the losses from black rot are reduced.

Fungicides containing chlorothalonil chlorothalonil base fungicides, as an active ingredient will help control Black rot and most other fungus issues that effect Pumpkins and Squash.

Anthracnose occasionally infects squash and pumpkin. Anthracnose, caused by a fungus similar to gummy stem blight, it is favored by warm temperatures and high humidity. Most commonly in the spring when the weather is cool and wet.

Lesions usually develop while fruit is in storage. On pumpkin, lesions are mostly circular, sunken, and measure 2 to 5 mm in diameter or larger. Because the anthracnose fungus overwinters in debris, a minimum 2-year rotation out of all cucurbits is required for control.

Fungicides are rarely used, even by commercial growers, they are of limited value against anthracnose – proper sanitation practices and crop rotation should suffice.

Powdery Mildew – The surface of affected leaves are covered by a white mass of the fungus, which has a powdery texture. Symptoms may also be found on petioles. Treat with Garlic GP: Vegetablle FungicideFungicide See Also: Milk for Powdery Mildew

Common Pumpkin and Squash Pests

Many insects will feed off Pumpkin and Squash, these are the more common ones.

Squash Bugs feed by sucking sap from the leaves and stems while injecting a toxic substance into the plant causing a wilting known as Anasa wilt.

Effective Controls are rotenone, pyrethrin, Neem Oil which prevents the larvae from developing normally, or insecticidal soap which smothers it.

Cucumber Beetles will feed on cucumber, as well as related crops such as pumpkin.

Squash vine borers are the larval stage of a moth

The body and wings of adult moths are colored with red and black scales, and they are frequently mistaken for wasps

This species of moth is active in the daytime

The larvae have been known to feed around the clock

A number of products are available that will help control squash vine borers. Sevin, Asana, Pounce, are a few Rotenone Rotenone is the eco-friendly alternative.

Aphids are Yellowish-pink to pale green plant lice that suck plant juices. They are a soft-bodied, oval/pear shaped insects and are commonly found on nearly all varieties of plants, vegetables, field crops, and fruit trees.

NeemNeem oil is helpful in controlling Aphids and other pests.

Other Insects which are known to feed on Pumpkin and Squash are

  1. Cutworms
  2. Wireworms
  3. Leaf Hoppers
  4. Maggots

Companion Planting for Pest Control

Corn when companion-planted with squash or pumpkin is said to disorient certain insects pests and protect the vining crop . In reciprocation, pumpkins prickly vines are said to discourage raccoons and some rodent pests from chowing down on the sweet corn.

I don’t have much of a raccoon problem anymore {my 2 German shepherds handled that issue very nicely } but a few years back – I did , my corn was unmolested – whether it was due to this planting scheme or just dumb luck I can’t say for certain.

Radishes planted amongst cucumbers are proven to repel cucumber beetles. Nasturtium and Savory are also believed to repel cucumber beetles. Both would fare well planted with or near cucumber patches.

Marigold planted in proximity will deter many varieties of beetles. Nasturtium as well as Oregano deters beetles and several other harmful insects.

Avoid planting Pumpkin in proximity to, or in the same plot that Potatoes have recently grown – recent being the last several seasons.

If feasible, don’t plant squash, cucumbers or pumpkin on the same plot more often than once in a three year cycle.

See: When to Plant Pumpkins in North Carolina