I sure hope that you can help me. I have a tropical hibiscus. It keeps dropping its flower buds. It did have a lot of aphids, but I sprayed it regularly and now the bugs seem to be gone. However, the buds still drop. Can you give me some suggestions to help my poor hibiscus?
Tropical hibiscus is an excellent plant for adding bold color to your garden or patio.
In my garden, I have freezing winter temperatures so I treat these exotic beauties as annuals. However, many people who live in similar climates want to save their hibiscus, so they simply bring the plant indoors for the winter.
Hibiscus flower buds are very sensitive. Stress from too much or too little water, over fertilizing or insect infestation can cause buds to drop before opening. Double flowering varieties are more susceptible to bud drop.
It may be possible that your hibiscus is still recovering from the aphid infestation and subsequent treatment. To lessen the shock it is important that plants are well hydrated when applying pesticides and that the treatments occur either in the early morning or late afternoon when temperatures are below 80 degrees F.
If the problem persists, check your watering. Hibiscus will not tolerate wet feet, so be sure that the soil drains well. When growing in containers a soilless potting mix is preferable. These plants also suffer when allowed to dry out in hot weather. A 2 to 3 inch layer of mulch will help keep the roots cool and retain moisture.
Hibiscus are heavy feeders and should be fertilized every 7 to 10 days during the spring and summer with a product that is high in phosphorous. For potted plants use a water-soluble 20-20-20 blend. Slow release fertilizers are also recommended.
Hibiscus thrive in full sun but for the best bloom production give them shade during the hottest part of the day if your garden experiences temperatures above 90 degrees F.
And if you want to overwinter your hibiscus, move your plants indoors before temperatures fall below 50 degrees F.