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Thursday - August 08, 2013

From: Round Rock, TX
Region: Southwest
Topic: Soils, Herbs/Forbs
Title: Soils for spiderwort from Round Rock TX
Answered by: Barbara Medford


We have spiderworts growing naturally in our backyard. We put a large circle around them them with limestone rock (as our beds have) to make their own bed as they clumped in one area. What kind of soil should we use to build up the bed? Every website I have explored says something different.


There are 16 members of the genus Tradescantia (spiderwort) native to North America, of which 10 are native to Texas. Seven of those are native to Central Texas, 2 specifically native to Williamson County. Each and every webpage we visited had this sentence on it:

"Tradescantia species will hybridize in just about any combination." Also, they are considered weeds by many farmers and gardeners. So, we don't know why we spent the time figuring out which spiderwort you might have in your garden, their needs all seem to be alike. And, each webpage had this information on it:

"Warning: All parts of this plant contain volatile oil that can cause severe skin inflammation, itching, and blistering on direct contact or if borne by sooty smoke. Washing thoroughly with soap or swabbing with alcohol immediately on exposure removes the oil irritant. The berries are poisonous if eaten."

We chose Tradescantia gigantea (Giant spiderwort) as a sample, because it is very showy and its webpage had more information on it. Here are the Growing Conditions specified:

"Growing Conditions

Water Use: Medium
Light Requirement: Sun , Part Shade
Soil Moisture: Moist
Soil Description: Clay, Clay Loam Medium Loam, Sandy Loam, Sandy, All soils.
Conditions Comments: Tradescantia gigantea has a dainty, three-petal flower with slender, hairy stamens. The flower color can be an indicator of the PH of the soil. Acidic soils produce bluer flowers, while more alkaline soils create varying shades of pink and purple."

It looks to us as though these plants will grow anywhere in just about all soils and conditions. Perhaps you might consider an electrified fence instead of rocks around it. We don't believe you need to worry about it thriving.


From the Image Gallery

Giant spiderwort
Tradescantia gigantea

Giant spiderwort
Tradescantia gigantea

Giant spiderwort
Tradescantia gigantea

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