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Monday - August 11, 2014

From: Austin, TX
Region: Southwest
Topic: Rain Gardens, Planting, Herbs/Forbs
Title: Growing Texas star hibiscus in Central Texas
Answered by: Guy Thompson

QUESTION:

Hi there, I purchased a beautiful Texas Star Hibiscus that I want to plant in my yard. Unfortunately, my yard being in Travis Heights, I hit a lot of caliche when digging. To plant some other native trees such as wax myrtles, I hired a professional to dig through the caliche and plant them. However, since the hibiscus is a shrub (only expected to grow to about 6 feet), I'm trying to figure out what the best way to plant it is. How deep do I need to dig? In other words, for a 6' shrub, how long do the roots grow? Also, what do I need to do to counter the alkaline pH that this caliche introduces? Any tips will be appreciated! Thanks! Jay.

ANSWER:

The Hibiscus coccineus (Scarlet rosemallow), or Texas star hibiscus grows wild in damp or even marshy places.  Although it can survive dry soil you would be well advised to dig a generous hole (3-4 ft in diameter and 2 ft deep) and fill it with rich garden soil with sulfur, aluminum sulfate or other soil acidifying addition.  This will prevent the plant from contacting the caliche that it would not like.  As advised in this web site, provide ample water and good drainage.  To achieve maximum bloom, plant in a sunny spot.  You should have good success.

 

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