Texas sage

Leucophyllum frutescens

also called cenizo, barometer bush, texas ranger, purple sage

The silver barometer bush of Texas and the Southwest: felted gray leaves all year, and sudden all-over flushes of orchid-purple bloom that follow the humidity a few days ahead of summer rain.

Light Full sun, the harder the better
Water Almost none once established; this is the shrub the sprinkler kills
Hardiness Hardy
USDA zones 8a–11a
Height 1.5–2.5 m
Spread 6 ft 7 in
Spacing 1.2–2 m
Sow depth From a container plant in fast-draining ground
Root depth 24 in–5 ft
Type
Shrub · Perennial
Botanical family
Mixed / other
Foliage color
Silver and gray
Flower color
Purple and violet · Pink
Sunlight
Full sun, the harder the better
Watering
Almost none once established; this is the shrub the sprinkler kills
Soil
Poor, alkaline, sharply drained; caliche is fine, compost is not
Feeding
Gentle all-organic
USDA zones
8a–11a
Frost tolerant
Yes
Plant out
at the last spring frost
Plant spacing
4 ft 11 in
In-row spacing
3 ft 11 in
Between rows
6 ft 7 in
Square-foot density
Not suited to SFG
Root system
Woody, with a taproot it keeps
Working depth
24 in–5 ft
Can reach
10 ft down where the soil allows
Spread
10–16 ft across, about 1.5–2.5× the width of the plant

It anchors downwards as well as sideways, which is what lets it stand in a gale and what makes it hate being moved. Plant it small: past a few years in the ground a taprooted tree transplants badly, and often not at all.

The habit is Texas sage’s own; the figures are what that habit usually comes to at this size, not a measurement of this species. Roots follow the soil either way: a compacted pan, a high water table or heavy clay stops them well short of any of it, and deep open ground lets them go further.

When
Not harvested. If it must be shaped at all, thin it in late winter and then leave it alone.
What to look for
A genuinely overgrown plant, which takes years. Bare inner wood means it has been sheared into a ball and needs rebuilding.
How to harvest
Thin whole stems at the base to keep the airy silver cloud; never box it. A sheared one goes leafless inside and blooms only at the skin. Water it almost never; the bloom rides the rain, not the hose.
How often
Every few years at most.
Storing the crop
Nothing to store. When it turns purple ahead of a storm, believe it over the forecast; the neighbors' plants will confirm.
  • Generally trouble-free No notable pest or disease problems when grown in the right conditions — one of the easy ones.

The rain-bloom is real: rising humidity and a pressure drop trigger the flush, so the neighborhood turns purple together before a storm. It is not a sage at all, and the fastest way to kill one is the ordinary kindness of irrigation and mulch.