My Hoya Is Not Blooming

Cultivation

• Hoya flowers are sensitive to under- and over-watering. Allow the soil around the plant to dry out completely before you apply more water to the ground during winter months. When watering, moisten the soil to a depth of only 1 inch. In summer, water the soil thoroughly and do not allow it to dry completely before you water again. If hoyas are not blooming and soil moisture is well-regulated, the problem may be lack of light. Give the flowers direct, full sunlight throughout the spring and summer to ensure proper flowering.

Care

• Hoya plants naturally go dormant during winter. Decrease fertilization and watering of the plant as the weather turns cool and the plant begins to shut down. Rest is essential to the hoya plant; a full period of dormancy is needed to allow it to blossom to its full potential the next growing season. Once flowers bloom and subsequently wilt, remove the old blossoms but do not disturb the woody spur where the flowers grow. New flowers will grow on this spur next spring. If the woody spur is cut or pruned away, flowering could be delayed or halted.

Disease

• Disease may prevent normal flowering or even prove fatal to the plant. Botrytis blight creates large, grey legions on the plant. Humid, wet foliage encourages botrytis blight, a fungal disease. Stem and root rot, another type of fungal problem, may also keep hoyas from flowering. The rot will make the stems weakened and brown. The leaves may also turn brown or develop red legions when stem and root rot are present. Rot is a common symptom of over-watering. Fungicides may be used to treat diseases that may prevent or otherwise affect normal blossoming of hoya plants.

Pests

• Hoya plants are susceptible to pest attacks from many insects. Aphids, which feed on the nutrients inside the leaves of hoya plants, may cause distortion of new growth that prevents flowering. When infestation is heavy, the plants may become stunted. Fungus gnats feed on the roots and leaves of the hoya. Gnats are not generally fatal to hoyas, but heavy feeding could weaken the plants and prevent blossoms from appearing. Mealybugs are capable of killing hoya plants by spreading sooty mold, a fungal disease that affects foliage and flowers. Thrips feed on both leaves and flowers, creating silvery legions and distorting growth. Thrips also transmit the damaging tomato spotted wilt virus. Use pesticides to prevent and control insects on hoya plants.