Leucophyllum

( lew - koh - FILL - um )

At-A-Glance Information

Commonly called Texas Ranger, Silverleaf, or Barometerbush, this genus of evergreen shrub is compact but slow growing and is native to the southwestern United States and northern Mexico. Foliage is silvery or green and flowers usually bloom after warm season rains. They need very good drainage but can tolerate a fair amount of heat, wind and can take alkaline soils. Great as an informal or clipped hedge, and a wonderful addition to xeriscapes.

Leucophyllum Species and Varietals

The genus Leucophyllum contains about a dozen distinct species, and is a member of the plant family Scrophulariaceae. The genus, although commonly called a Sage, has no relation to true Sages (Salvias). Leucophyllum is closely related to Verbascum, Buddleja, Sutera, and Nemesia. The common name Barometerbush comes from the fact that these shrubs can sometimes forecast the weather; they will bloom just a few days before rains appear (when humidity rises). Texas Ranger grows best in USDA hardiness zones 8-10 or Sunset growing zones 7-24, though this can vary slightly depending on the species. For more information, consult the descriptions below. To find your zone, click here: Zone Map.

Leucophyllum candidum (Violet Silverleaf, Brewster County Barometer Bush, Violet Texas Ranger, Silver Cloud Sage)
This species of Silverleaf reaches 5 feet tall and wide, and has silvery leaves and deep purple flowers. Cultivars include 'Silver Cloud' (with profuse blooms and whitish foliage), 'Thunder Cloud' (pictured; a 3-4 foot tall and wide shrub with deeper purple blooms that are closely set), and 'Microburst' (dwarf to 3 feet tall and wide). This species grows well in USDA hardiness zones 8-11.

Leucophyllum frutescens (Texas Ranger, Texas Sage, Cenizo, Texas Barometerbush, Ash-Bush, Wild Lilac)
This species grows well in USDA hardiness zones 8-11 or Sunset growing zones 7-24, H1 and H2 and reaches 6-8 feet tall and wide at maturity. Foliage is grey and flowers are light purple in the straight species. This species is considered invasive in Anguilla and other Caribbean Islands. Cultivars are listed and described below:

'Alba'
4-6 feet tall with white flowers.

'Compacta'
3-5 feet tall and wide with magenta-purple flowers.

'Desperado'
4-6 feet tall and wide with vivid purple flowers.

'Green Cloud'
Rich green foliage and vibrant rose-purple blooms.

'Los Alamitos'
Vibrant pink-lavender flowers on a 6-8 foot shrub.

'Silverado'
4-6 feet tall and wide, silver grey foliage and bright violet-pink blooms.

'White Cloud'
Grey-green foliage and white to pale lavender blooms. 4-8 feet tall and wide.

Leucophyllum laevigatum (Chihuahuan Sage, Chihuahuan Rain Sage, Chihuahuan Ranger)
This plant has an open, angular growth reaching 4 feet tall and 5 feet wide. Leaves are small and dark green, flowers are lavender and bloom profusely. This species grows well in USDA hardiness zones 8b-10b. Cultivars include 'Purple Rain' (with denser, upright habit and violet flowers), 'Summer Snow' (natural, loose form with white flowers), and 'Heavenly Cloud' (with upright, spreading habit and light purple to lavender blooms).

Leucophyllum langmaniae (Langman's Sage, Rio Bravo Sage, Rio Bravo Ranger, Braue River Sage, Monterey Rain Sage, Texas Sage)
This species grows well in USDA hardiness zones 7a-11b and reaches up to 5 feet tall and just as wide at maturity. Plants have a dense habit and bright green leaves. Flowers are lavender and bloom profusely over a long season in summer. Varieties include 'Lynn's Legacy' and 'Rio Bravo' (with rich green foliage on a plant that keeps a tidy rounded form). This species is named for botanist Ida Kaplan Langman.

Leucophyllum pruinosum (Fragrant Rain Sage, Bubblegum Sage, Sierra Bouquet Texas Sage)
This species grows well in USDA hardiness zones 8a-11b and reaches up to 6 feet tall and wide with an open growth habit. These shrubs have silvery foliage and purple flowers that are strongly fragrant and smell of bubblegum. Variety 'Sierra Bouquet' (pictured) is especially fragrant.

Leucophyllum revolutum (Little Leaf Ranger, Texas Sage, Texas Ranger, Houdini Sage, Cenizo, Barometer Bush)
This slow grower reaches 4 feet tall and 4-5 feet wide with light green, somewhat fleshy foliage. Purple flowers bloom in fall. Cultivar 'Houdini' is a popular garden ornamental with larger, showier flowers than the straight species. Little Leaf Ranger grows well in USDA hardiness zones 8-10.

Leucophyllum zygophyllum (Blue Ranger, Blue Rain Sage)
Blue Ranger grows well in USDA hardiness zones 8-11. It forms a shrub to 3 feet tall and wide. Grey-green cupped leaves contrast well against light blue to purple flowers. Blooms tend to appear before rainstorms. Cultivars include 'Cimarron' (with cupped leaves and blue-purple flowers), 'Laredo' (with a rounded habit and showy rebloom), and 'Sierra Fresca' (with a somewhat cascading habit that turns upright with maturity).

Caring for leucophyllum

Plant Leucophyllum shrubs in a spot in your garden that receives 6-8 hours of sun each day. They love being in full sun exposure, but can take some partial shade and still flower well. Ensure that soil is well-draining, or amend to make it so. Leucophyllum shrubs prefer soil with a pH of between 6.6 and 8.5. Water regularly during the first growing system, and afterwards are drought-tolerant, only requiring occasional waterings during the warm summer months. Fertilize with a balanced, slow-release fertilizer in early springtime to support new growth if the plant seems to be struggling or if soil is particularly poor, otherwise these shrubs do not need supplemental feedings and over-fertilizing will cause legginess.

Texas Sage is hardy down to 10 degrees Fahrenheit, and is tolerant of warm temperatures, as well. Considered easy to care for, these plants do not need to be pruned unless they are being used as a hedge, and have a beautiful, bushy growth habit. If plants are getting too old and straggly, they can be pruned back hard and they will come back the following season, though they may not flower as well until the next year. The best time to prune is after the active growing and flowering period for shaping, and in late wintertime for any rejuvenation prunings that need to happen. These shrubs have a life span of between 10 and 30 years in the garden.

Propagation

Leucophyllum can be propagated either by using cuttings or from seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the cutting method. If you would like to experiment and see what plant you can grow from seed, just keep in mind that it will not necessarily be the same as the parent plant. To propagate your Caesalpinia, follow the instructions below:

Propagating Leucophyllum by Cutting

Gather your materials. You'll need a clean, sanitized, sharp pair of garden shears, rooting hormone, a pencil, and a 3-inch pot filled with well-draining compost or other organic material. A good substrate for propagation of cuttings is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
In spring or early summertime, choose the plant that you'd like to propagate. Ensure that this plant has had a good watering the night before, as this will improve the chances your cutting will take root. Cut one or more softwood 6 inch portion(s) of the end of a non-blooming branch and strip the leaves off of the lower half. Make a hole in your planting medium by pushing your pencil into the soil. Dip the end of the stem in rooting hormone, and plant it in your pot. Fill in soil around the cutting to support it, but do not pack it down too much.
Moisten with water, and ensure that the pot has good drainage. Your pot should be kept in warm, sunny conditions indoors (and not in direct sunlight). Water whenever your soil is dry under the top layer. After about four to six weeks have passed, your cutting should be rooted. When you notice new growth, you'll know you have roots.
Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring, when you can transplant it to its new home. Ensure that the last frost of the year has occurred before doing this, as it can seriously damage your new shrub.

Propagating Leucophyllum by Seed

Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. The best potting medium for seed germination is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
Harvest your seeds. The seed heads are left behind after flowers have faded. Once they have dried out and begun to split open, you can harvest the seeds inside. Cut them off of the plant, placing them in a paper bag. Harvest as many as you can, and place the paper bag in a dry, cool, dark area. They will begin to split open and release the seeds contained inside. Once they have been released, take them out of the bag and put them in a container so you can work with them.
Water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them with soil and water with your spray bottle. Place your tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 7-14 days from sowing. Once you begin to see seedlings sprout and they are able to be handled, transplant them to their own individual 3-inch pots, filled with the same potting medium as described in Step 1. Loosen the seedlings from the potting medium by digging down with the tines of your fork about an inch and a half, gently working the seedling up until it is out. Then, replant the seedling in its individual pot.
Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home.

Leucophyllum seeds are contained inside of seed pods that are left behind on branches after flowers have faded.

Leucophyllum seeds.

Problems and Pests

Certain Leucophyllum species are considered invasive in some regions; see the species descriptions above for more information. Check with local authorities before planting. Leucophyllum shrubs are rarely bothered by pests or disease, but it is good to look out for the following: