Plants in hot and tropical climates have to have a great strength. These plants may need to be drought tolerant as well as heat tolerant. Heat tolerance will make them less likely to wilt, wither, and die in high temperatures. For native shrubs that have this heat tolerance, there are some good choices such as the Southern Bush Monkeyflower, Creosote Bush, and Texas Ranger.
Common Name: Southern Bush Monkeyflower
Synonyms: Mimulus longiflorus
Description: A shrub that grows 1 to 3 feet high and 1 to 3 feet wide, Southern bush monkeyflower has many branches. Leaves are lance-like and light green. Flowers are tubular and look like monkey faces. Blooms are white, orange, yellow, or red and will flower between March and July.
Planting Guide: Diplacus longiflorus prefers partial shade and dry rocky soil. It tolerates cold, heat and drought.
Propagation: Southern bush monkeyflower is propagated by seed and tip cuttings. Seed does not need any pretreatment before planting.
History: It makes a good addition to a bird garden and has a high deer resistance.
Warnings: This is a plant that needs regular pruning and shaping or it gets brittle.
Distribution: Diplacus longiflorus is found in CA.
Common Name: Creosote Bush, Guamis, Greasewood, Hediondilla, Governadora
Synonyms: Larrea tridentata var. tridentata, Larrea divaricata
Description: This shrub grows 3 to 5 feet high typically or can get as large as 10 feet tall. Stems are angular and slender with green leaves that are aromatic. Flowers are yellow and small, blooming between March and September. Blooms are prolific. Fruits are white, pea-sized, and fluffy. It is an evergreen shrub.
Planting Guide: Larrea tridentata prefers dry well-drained soil and partial shade. It is both cold and heat tolerant.
Propagation: Creosote bush is propagated by seed. It will need scarification of the seed coat’s hard layer and distilled water soaking. It may be done via cuttings, but it is harder to root this way.
History: Leaf decoctions have been an herbal remedy as emetics and antiseptics.
Warnings: The creosote gall midge fly can cause leafy galls in the plant.
Nothing will grow underneath a creosote bush because of the toxins it gives off. There is the potential for poisoning due to toxins in the plant, do not ingest.
Distribution: Larrea tridentata is found in AZ, CA, NV, NM, TX and UT.
Common Name: Texas Ranger, Purple Sage, Texas Sage, Texas Silverleaf, Texas Barometer Bush, Cenizo
Synonyms: Terania frutescens
Description: A small evergreen shrub, the Texas ranger grows 2 to 5 feet high. Flowers are pink-lavender and leaves are silver gray or green. Flowers are bell-like and bloom throughout the year. Even though it is evergreen, it may lose some leaves during a very cold winter season.
Planting Guide: Leucophyllum frutescens needs sun or partial shade and a rocky dry well-drained soil. It is both heat and drought tolerant.
Propagation: Texas ranger is propagated by semi-hardwood cuttings, softwood cuttings and seed. Seed can be stored in a dry cool place.
History: It is a larval host for both the Calleta (Eupackardia calleta) silkmoth and the Theona checkerspot (Chlosyne theona) butterfly.
Warnings: May get cotton root rot if the soil stays moist and isn’t well draining.
Distribution: Leucophyllum frutescens is found in TX.