Symptoms may occur at any stage in the development of the fruit, but first symptoms usually are seen when the fruit is one-third to one-half full size. As the name of the disease implies, symptoms appear only at the blossom end of the fruit. Initially a small, water-soaked spot appears, which enlarges and darkens rapidly as the fruits develop. The spot may enlarge until it covers as much as one third to one-half of the entire fruit surface, or the spot may remain small and superficial. Large lesions soon dry out and become flattened, black, and leathery in appearance and texture.

This disease does not spread from plant to plant in the field, nor from fruit to fruit in transit. Since it is of a physiological nature, fungicides and insecticides are useless as control measures. The occurrence of the disease is dependent upon a number of environmental conditions, especially those that affect the supply of water and calcium in the developing fruits. Factors that influence the uptake of water and calcium by the plant have an effect on the incidence and severity of blossom end rot. The disease is especially prevalent when the plant is rapidly growing and then experience a sudden period of drought. When the roots fail to obtain sufficient water and calcium to be transported up to the rapidly developing fruits, the tomatoes become rotted on their basal ends. Another common predisposing factor is cultivation too close to the plant; this practice destroys valuable roots, which take up water and minerals. Tomatoes planted in cold, heavy soils often have poorly developed root systems. Since they are unable to supply adequate amounts of water and nutrients to plants during times of stress, blossom end rot may result. Soils that contain excessive amounts of soluble salts may predispose tomatoes to the disease, for the availability of calcium to the plants decreases rapidly as total salts in the soil increase.

Control of blossom end rot is dependent upon maintaining adequate supplies of moisture and calcium to the developing fruits. A soil test, available through Penn State, can determine the calcium and phosporous levels of your garden soil. Phosporous is necessary for the plant to be able to absorb calcium from the soil. A low pH level can also inhibit calcium absorbtion. Use a fertilizer low in nitrogen, but high in superphosphate, such as 4-12-4 or 5-20-5.

Tomatoes should not be excessively hardened nor too succulent when set in the garden. They should be planted in well-drained, adequately aerated soils. Tomatoes planted early in cold soil are likely to develop blossom end rot on the first fruits, with the severity of the disease often subsiding on fruits set later. Thus, planting tomatoes in warmer soils helps to alleviate the problem. Irrigation must be sufficient to maintain a steady even growth rate of the plants. Mulching of the soil is often helpful in maintaining adequate supplies of soil water in times of moisture stress. When cultivation is necessary, it should not be too near the plants nor too deep, so that valuable feeder roots remain uninjured and viable. In home gardens, shading the plants is often helpful when hot, dry winds are blowing, and soil moisture is low.

Although differences exist among tomato varieties with respect to susceptibility to blossom end rot, no varieties as yet have commercially useful resistance.

Good luck!

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The squash vine borer is a common problem of squash and pumpkin and can also affect cucumbers, cantaloupe and melons.

The squash vine borer injures plants by tunneling through their stem. This damages the plant's ability to transfer nutrients. The feeding insect weakens the plant which increases the chance for secondary infections.

Plants damaged by the squash vine borer will wilt. Examination often reveals green-to yellow colored frass (insect excrement and debris) within the stem. Often frass will protrude from any damaged areas of the stem. If vine senescence occurs early, the borer may tunnel into the fruit.

The squash vine borer overwinters as a pupa. Pupae are about 2 centimeters long, silk lined, black and usually found in the soil.

In Pennsylvania adults emerge in mid-to-late June. The adult squash borer may be mistaken for a wasp. The front wings are a metallic green and the rear wings are transparent with black or brown margins and veins. Wingspan is approximately 2.5 - 4 cm. The body is orange and black, often in a ringed pattern surrounding the abdomen.

The adults lay eggs throughout July and August. Eggs are deposited on the stem immediately above the ground surface. They hatch in a week to 10 days to. Larvae then enter the stem immediately, leaving a small hole. The larvae will feed on the plant for approximately 4 weeks by continuing to tunnel through the stem of the plant. When they are ready to pupate the larvae will burrow into the soil and spin a cocoon. In Pennsylvania the squash vine borer only have one generation a year.

When infestations of squash borer are caught early it is often possible to save the plant. Where squash borer entry holes are detected, split the vine lengthwise and remove any observed borers. Entry holes are frequently just above where the vine breaks the soil. Use caution not to split any farther than is necessary to remove the insects. After careful inspection and removal of insects, place a few centimeters of moist soil over the split vine.

Gardens that have been attacked in the past by squash vine borers are more likely to have problems in the future. It may be possible to kill many overwintering pupae, thus reducing next year's population. Soil should be tilled after harvest then tilled again the following spring. This combination produces mortality from both the cold of winter and from difficulties escaping from the soil in the spring. Another cultural control is to destroy vines after harvest. This prevents borers still in the larval stage from completing their development.

As with all boring insects, sprays need to be timed to contact the insects before they bore into the plant. For this reason sprays on a weekly basis are NOT recommended.

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