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Monday - January 09, 2012

From: Marble Falls, TX
Region: Southwest
Topic: Seasonal Tasks, Herbs/Forbs
Title: Seasonal tasks for Big Red Sage and Tall Aster in Marble Falls TX
Answered by: Barbara Medford


I transplanted some Big Red Sage and Tall Aster into my raised bed garden in early summer this year. They've sent up lots of rosettes. Do I need to protect them from freezing in winter? Do I need to thin them and if yes, when? Thank you.


Salvia pentstemonoides (Big red sage) and Symphyotrichum praealtum var. praealtum (Tall aster) are two excellent plants for your garden, with fairly low maintenance needs. Both are native to Burnet County, so they are hardy in the USDA Hardiness Zone where they are growing. Both are perennials that die back to the ground and come up from the rosettes in the Spring and both thrive in sun or part shade. Don't worry about covering them in the ground. They are insulated by the warmth of the Earth; in fact, Big Red Sage is hardy from Zones 6a to 10b and Tall Aster grows as far north as Ontario in eastern Canada. Burnet County is in Zone 8b.

As far as thinning them, we would say you don't "need" to thin, you thin them when they are getting crowded or you need more plants in another area. We suggest you read this article on Caring for Your Perennials from Weston Gardens, especially this excerpt on time of thinning:

"Perennials, in general, should be transplanted during the season opposite of when they bloom. That is, transplant Spring and Summer-flowering perennials in the Fall and transplant Fall-flowering perennials in the early Spring."

Therefore, since the Big Red Sage blooms red in June to October and Tall Blue Aster blooms purple from October to November, both could be thinned in Spring.


From the Image Gallery

Big red sage
Salvia pentstemonoides

Spreading aster
Symphyotrichum patens var. patens

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