For:
By: Daniel E. Mullins
Extension Horticulture Agent
Hibiscus Provides Long Lasting Color in the Landscape
The use of Hibiscus shrubs in the landscape has increased greatly over
the past several years. They love hot weather, are well adapted to high humidity and flower throughout late spring and summer.
The genus Hibiscus contains about two hundred and fifty species of herbs, shrubs and trees that grow in the tropical and warm temperate regions. Both tropical and hardy species are used in landscapes along the northern Gulf coast.
One of the most cold-hardy species is Hibiscus syriacus, commonly known as Rose of Sharon or Shrub Althea. It is now available in several flower colors and in single or double forms.
Cotton Rose or Confederate Rose, Hibiscus mutabilis, is an old timey plant that is finding its way back into modern landscapes. Though usually freezing back each winter, it recovers each spring, forming a large informal shrub that yields spectacular late summer and fall color.
There
are six Hibiscus species that are native to
To many gardeners Hibiscus means Hibiscus rosa-sinensis, which is commonly known as the Chinese Hibiscus. This is the most popular and widely planted shrub of the tropics and has become quite popular in our area. There are hundreds of named varieties of tropical Hibiscus that include a full range of flower colors and sizes.
Anyone who grows the tender Hibiscus species and varieties should be cautioned that an extremely cold winter can completely kill them. That said, most beat the odds and recover each spring to continue flowering by May or June.
Hibiscus Growing Basics:
Light: The amount of sun required for optimal hibiscus growth and flowering differs with variety. Generally, half a day of direct sunlight is the minimum requirement.
Soil: A wide range of well-drained soils is acceptable if proper fertilization is provided. A soil pH of 5.5 to 6.5 is preferred. Hibiscus grown where the soil is naturally alkaline or where excessive lime has been applied may suffer from micronutrient deficiencies.
Planting: Container grown plants can be established any time during the year, but moving them from one location in the yard to another is best done during the cooler months. Avoid excessively deep planting. The planting hole should be about one foot wider than the root ball and slightly more shallow. Plants should be watered thoroughly immediately after planting and frequently enough to prevent wilting until they are well established.
Fertilization: Make three light applications of a complete
fertilizer during the growing season.
The last application of the season should be done no later than the end
of September in
Pruning: Clip away old flowers as soon as they fade. Any heavy pruning that is necessary should be done in early spring and should not be done late in the fall or during winter. Light pruning can be done during the season as needed to remove crowded branches, weak growth or extremely vigorous sprouts.
Additional information about
Hibiscus can be obtained from your local Extension office, nursery, garden
center or landscape professional. Web
users can obtain a copy of a seven page document, “Hibiscus in
Question of the Week: I have three pear trees that were pruned last winter. All of the fruit is on the lower part of the tree and there are long shoots that are growing straight up with no fruit. Isn’t it the wrong time to prune these long shoots?
Answer: These vigorous long
sprouts on pear trees are juvenile growth and are normal. This is a stage that pear trees must go
through. Do not prune these away, as
this practice will only cause them to repeat the process, keeping trees in a
juvenile stage. Pear trees require
little pruning, other than the removal of crowded branches.