Abortion in plants is premature termination of the development of pollen, gametes, embryos, seeds, fruits, flowers etc. There are several factors which lead to your fruit tree abortion. The most important step you can take to help you identify the cause of the problem is to seek the services of an extension officer especially one with good experience in horticultural crops in your region. Abortion may be due to environmental and cultural factors that can contribute to, or cause, flower bud abortion.

Insufficient light. Flowers require a relatively large supply of energy to develop normally. The energy can come from stored carbohydrates, such as from bulbs and tubers, and light that drive photosynthesis. When the amount of light is not sufficient to support the energy demands of the flowers, they can abort. Pruning is an effective method of increasing light to your plants.

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Temperatures. Low temperatures especially in highland areas can slow down pollen germination. Periods of low temperatures and overcast skies can cause flower drops. Fruits planted in highland areas always have a problem with slow flower setting and even flower abortion leading to failure in production of fruits.

Deficiency or excessive nutrients. Calcium is a macro nutrient and boron is a micro nutrient that is both components of cell walls and developing flowers. When deficient in one or both of these elements, flower buds can abort.

Too much compost. High application of compost mulch can also contribute to vegetative growth at the expense of flowering and fruit setting.

Fertilizers.  As it matures, it is important to apply some potassium and calcium.

Pollination. For any fertilization to be successful pollination has to take place. Bees and other nectar foraging insects such as the carpenter bees play an important role in cross-pollination of passion fruit flowers. Due to use of chemical pesticides in many farms, many bees are destroyed by the chemical spraying of such crops, in this case reducing their pollination services.

Water. Inadequate water especially at the crucial flowering stage can lead to flower drops. Lack of water can result in tiny fruits that are not marketable.

Birds and insect pests. Too many birds and insects pests can also cause flower drops in fruit orchard, they therefore be controlled mainly at the flowering stage.

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