In some parts of Texas, the summer atmosphere can be intolerably warm, sweltering, and muggy. The hot season lasts for about three challenging months each year, forcing many of the local flora and fauna to resort to desperate means of survival. In the gulf coast and southwestern regions of the state, for example, droughts can lead to wide expanses of parched and cracked land, leaving nary a drop of water for unfortunate seedlings.
As a result, many of Texas’ native plants have developed unique adaptations for staying alive in the absence of fresh water. Some of them develop strong tap root systems that are able to permeate through thick layers of dry soil. Others naturally enter a period of dormancy, leaving overhead shoots that have appeared to die back. Others exist as annual plants, taking root only when groundwater and rainfall levels have swelled.
As temperatures peak at around 32 – 38˚C (90 – 100˚F) from June to August, plants that are sensitive to heat may need to be brought indoors. To minimize the effort required to maintain a potted garden in the arid regions of Texas, it would be wise to cultivate heat-tolerant plants (for hardiness zones 7 – 9). Potted plants tend to be more susceptible to high temperatures, especially as the reduced amount of substrate limits their access to moisture.
1) Texas star cactus (Astrophytum asterias)
If you naturally have an appreciation for desert plants and their phenomenal adaptations, you’ll find that the Texas star cactus is a definite must-have in your garden. This dwarf cactus is beloved by many plant collectors for its petite size, ease of care, minimal requirements, and stellar features. Though it may be largely unnoticeable in its wild environment where it tends to mimic the appearance of a sunken stone, it tends to look valuable and delicate in a pot or container.
In the arid regions of South Texas, this cactus occurs in scrubs with sparse vegetation. Its roots, which can quickly rot and die back in waterlogged conditions, favor sandy to loamy substrates due to their porous nature. In prolonged droughts and in intense heat, the roots tend to pull the bulbous shoot further into the soil. This helps protect the plant from becoming scorched.
After periods of generous rainfall, mature star cacti begin to produce solitary bulbs that are relatively large compared to the full size of the plant. When present in clusters, the yellow blooms can collectively cover the entire mother shoot. From March to May, potted specimens of this species are likely to steal the show in a container garden.
2) Autumn sage (Salvia greggii)
Though this charming species is referred to as the “autumn” sage, its delicate flowers may begin to appear in early summer. Its bright shades of scarlet, apricot, violet, pink, and white seem to herald the onset of significantly warming temperatures and the swarms of pollinators that come with them. This perennial’s most popular cultivars, which are known for blooming profusely and for having multi-colored petals, are perfect for pot or container cultivation.
The autumn sage’s full size and density of inflorescences are largely influenced by growth conditions. When provided with full sun, warm temperatures, exposure to many pollinators, and ample nutrients in the substrate, autumn sage can grow to about 4 feet (1.2 meters) tall. In warm climates, its shoots are nearly evergreen and its bloom period may begin as early as spring.
In optimal conditions, the autumn sage can grow remarkably fast. Some horticulturists opt to cut down the shoot once the flowering period has ended. This encourages healthy new growth and may stimulate an even more vigorous bloom in the succeeding spring. To draw attention to the features of this Mexican salvia, use pots of various cultivars to create a colorful border.
3) Ghost plant (Graptopetalum paraguayense)
Named for the ghostly pallor of its thick foliage, the ghost plant is one of the most commonly cultivated succulents in the US. Remarkably easy to care for and propagate, its thick, trailing shoots can creep over dry substrates and send out new roots along their nodes. Offsets are rapidly produced by plants that are rooted into periodically moistened, well-draining soils.
As the shoots may eventually grow toward and over the edges of a pot, this species can be cultivated as a cascading succulent from hanging pots. Its young offsets and cuttings can then be rooted as solitary rosettes in smaller pots. The leaves, which look pale due to a protective layer of natural wax, develop subtle pink hues in excessively dry and hot conditions. When they are situated in filtered or partial sun, they may develop a bluish tinge.
In spring, mature ghost plant rosettes develop floral stalks that may be several times the full height of the plant. These bear white to yellow, star-shaped blooms on clusters of branching inflorescences. During the growth period, it may be necessary to consistently water the substrate. However, the soil must be allowed to dry out completely in between watering sessions.
4) Red yucca (Hesperaloe parviflora)
The red yucca is not actually a true type of yucca. Its leaves may appear to be a cross between those of desert yuccas and naturally thin aloes. They arise in a basal rosette formation, hiding a short, woody base. In warm climates, the grass-like leaves are evergreen, drought-resistant, and tolerant of full sun exposure. Depending on ambient conditions, the light to deep-green leaves may measure up to 3 feet (91 cm) long.
Also referred to as the false yucca or coral yucca, this highly textural species can be cultivated in pots of just about any size. Their rosettes can seemingly fill out medium-large pots as the leaves arch toward the edges. Highly adaptable to well-draining soils, this species is a common candidate for filling out gaps in desert gardens or xeriscaped containers.
If pets and young children frequently visit your potted garden, consider growing this plant as a spineless alternative to true yuccas and agaves. It is often treasured as a low-maintenance and heat-resistant native plant. With due care, it should reward you with branching inflorescences of red to yellow flowers. These unfailingly attract hummingbirds and butterflies to the garden.
5) Texas lantana (Lantana urticoides)
Lantanas are arguably some of the best flowering shrubs for regions that experience markedly warm summers. With features that look undeniably productive and vibrant even in the sweltering heat, the Texas lantana can be propagated to thrive in large pots or containers. Its mature stands can be annually pruned back to strengthen the main shoot and increase the density of branches and leaves.
Tolerant of poor soils, this deciduous shrub thrives best in USDA hardiness zones 8 – 11. Its rough, toothed, and bright green leaves favor full sun exposure. From spring to fall, bouquets of colorful flowers appear on both mature and young branches. These possess tiny, yellow-to-orange blooms which gradually deepen in color as they mature. A single cluster of blooms can display a gradient of colors.
The Texas lantana grows to a full height of about 2 – 3 feet (61 – 91 cm), but a single, healthy shrub can have an impressive coverage of about 4 to 6 feet (1.2 – 1.8 meters). Of course, the spread is limited by the width of the pot and the amount of substrate in which the shrub’s roots can comfortably lengthen. To prevent the branches from overcrowding, aim to cut back or divide potted lantanas.
6) Agave ‘Blue Glow’
Developed by David Verity in the 1960s, Agave ‘Blue Glow’ is a cross between A. attenuata and A. shawii. It possesses a combination of the best features of these parent plants. Its frosted leaves seem to glow with the loveliest blue-green hues. Oriented upward in a sharp yet graceful manner, each tapered leaf has toothed, reddish-brown margins.
This agave hybrid is suitable for pot or container cultivation due to its manageable size. When provided with ample space, its mature rosettes measure around 1 – 2 feet (30 – 61 cm) tall and 2 – 3 feet (61 – 91 cm) wide. To accentuate their sculptural features, aim to situate them in front of textural stands of desert plants. Some landscapers choose to grow them as clumps in the foreground of larger types of agaves.
Though the ‘Blue Glow’ is drought-resistant much like its parent plants, it does benefit from being consistently watered during its peak growth period. Its young specimens also tend to require more water prior to becoming fully established. Deep, periodic irrigation should promote the growth of new leaves and prevent older ones from drying out.
7) Yellow bells (Tecoma stans)
A member of the Bignoniaceae or trumpet vine family, Tecoma stans is a semi-evergreen perennial. Also known as yellow bells and yellow trumpetbush, this drought- and heat-tolerant species can be cultivated as a shrub or as a small tree. Remarkably hardy, it can grow quickly and may potentially outcompete slower-growing herbs. Restricting the spread of its roots within a pot or container should help minimize its spread.
From spring to fall, branches of yellow bells tend to be covered in clusters of bright, trumpet-shaped blooms. These attract all sorts of butterflies, bees, and birds (including hummingbirds) to the garden. Able to tolerate full or partial sun, the branches stay densely leafy all throughout the growing season. The deep-green leaflets serve as a contrasting backdrop to the yellow flowers.
Usually cultivated as an ornamental plant in private gardens, parks, and along streets, yellow bells can effectively adorn rocky and dry landscapes. To maximize its growth and flowering rates, make sure it receives at least 6 hours of direct sun per day. Ensure that the moisture-sensitive roots stay healthy by allowing the substrate to dry out completely in between watering periods.
8) Rose vervain (Verbena canadensis)
Low-maintenance, effortlessly elegant, and perfect for all sorts of gardens, the rose vervain is frequently cultivated as a potted annual. This verbena produces vibrant clusters of pink to purple flowers from late spring to late summer. The fragrant blooms attract many pollinators and beneficial insects to the garden, thereby increasing its diversity and its value to wildlife.
Hardy to USDA zones 5 – 9, the rose vervain is remarkably resilient. This tender plant is able to tolerate high heat, dry conditions, and rough substrates. To maximize its growth and flowering rates, however, its potted specimens should be provided with ample moisture through summer. If the soil is kept dry for lengthy periods, verbena shoots may undergo significant leaf loss.
In warm regions of Texas, where winter temperatures rarely dip to below 5˚C (41˚F), this species may persist as a short-lived perennial. Make sure to deadhead its spent floral stems to maintain its compact growth habit and encourage a longer bloom period. If you’re after an award-winning cultivar of this species, look for ‘Homestead Purple’.
9) Sand aloe (Aloe hereroensis)
The sand aloe is a fantastic addition to semi-arid or arid gardens in USDA hardiness zones 9 – 11. This evergreen succulent has foliage and blooms that are constantly worthy of being inspected and photographed. While it can grow quite well rooted directly into the ground, it is often situated in pots due to its small size (compared to larger aloes). Mature rosettes of this species rarely measure more than a foot tall.
As indicated by its common name, this lovely aloe favors sandy substrates, where its roots rarely have to suffer due to poor aeration and drainage. Given a slightly alkaline substrate and occasional yet deep periods of seasonal irrigation, its tapered leaves can form structurally eye-catching rosettes. Under full sun, the leaves develop muted blue-green hues and rows of cream-colored speckles throughout their upper and lower surfaces.
The branching inflorescences of this species appear from June to September. They are borne on floral stalks that grow to about 2 – 3 times the height of the rosette. Orange, deep red, and magenta flowers densely surround the tips of floral stalks. They may be numerous and crowded enough to seem to defy gravity!
10) Pentas (Pentas spp.)
Although pentas are not native to North America, they are frequently cultivated in warm regions of the continent. Their leaves and densely clustered blooms seem to glow in gardens that experience hot and humid summers. If your landscape could use some soft hints of color, consider cultivating a few pots of this genus’ most prized cultivars.
In warm parts of Texas, pentas can thrive as potted perennials. Ideally, their stands should be started or outplanted in late spring or whenever ambient temperatures have begun to warm considerably. A well-draining substrate and full sun exposure are key to improving the toughness of both the roots and branches. Come summer, established plants should begin to produce their signature clusters of star-shaped blossoms.
If temperatures are agreeable throughout the year, pentas can bloom well into moderately warm winters. Their nectar-rich blooms are likely to attract many butterflies and hummingbirds. Penta lanceolata, or Egyptian starcluster, is a common choice for potted Texan gardens.
