Early Summer Scorcher in Houston, Texas! On Saturday, June 29, 2013, Houston’s official high temperature was a June record of 107F!
When temperatures get over 100F, many tropical hibiscus plants left in full sun are going to wilt. By mid-afternoon, water will sometimes evaporate from leaves faster that the plant’s vascular system can transport water.
Young plants with long gangly branches, and which have not yet established vigorous root systems, are especially susceptible to wilting in extreme heat. There has also been some occasional discussion among hibiscus enthusiasts on the question of whether grafted plants are able to withstand stress & very hot weather as well as plants grown on their own root system.
If at all possible, provide shade for at least part of the day. Water lightly a couple of times each day to keep the soil slightly moist, and use mulch to help keep the roots cool.
Exposed pots will soak up heat from the sides, and quickly dry out the root system. Bury pots in the garden, or pile mulch around them, to keep root systems cool.
And, don’t forget to take care of yourself. If outdoors, drink LOTS of water, and watch out for warning signs of dehydration: light-headed or dizzy, nausea, dry-mouth, difficulty focusing thoughts. Be careful, extreme heat can be very dangerous to those who are not accustomed to it.