Gardening Guide

<< Back to Previous Page

Gardening with Texas Tough Perennials

What is the difference between an annual and a perennial?

Annuals are plants that bloom, set seed, and die in a single growing season. Perennials, on the other hand, are plants that return year after year–some may only come back for two or three years while others will keep returning for decades. Some perennials are evergreen, but most go dormant in the Fall and return in the Spring from the roots.

How should a Texas gardener start a perennial garden?

Start with a master plan. Know the layout and dimensions of your garden. Know where, when, and for how long sunlight hits your garden. Choose plants accordingly, giving large perennials plenty of room to mature and arranging for many perennials to be planted en masse for greater effect. For the sunny perennial garden it is best to choose plants that bloom at different times of the year to create a dynamic garden with successive waves of color. For shady perennial gardens where flowering perennials are limited, focus on choosing plants with different foliage textures and colors.

Follow up the master plan with thorough bed preparation. North Texas is notorious for its alkaline, clay soil, and to fix the sins of our soil you will need two things: expanded shale and compost. Creating raised beds or berms is also recommended.

Expanded shale is a gravel-size rock that has been heated to a high temperature to create air pockets within that help to break up and aerate clay soils, aid in moisture retention and soil drainage. Expanded shale only needs to be added to the soil once.

Compost is organic matter that has undergone an accelerated decaying process in order to be used as a fertilizer and soil conditioner. Compost can be made at home or can be conveniently purchased in bags. Commonly sold composts include: cotton burr blends (Back to Earth) and cow manure.

To add these soil amendments, spread a 3 inch deep layer of expanded shale over the entire flower bed, and till the shale into the soil to a depth of 6 to 8 inches. Two or more passes may be needed to break up the clay soil sufficiently. Repeat the process by tilling in a 3 inch layer of compost.

How should a perennial garden be maintained?

Most perennials should be planted and fertilized regularly with a well-balanced, slow-release fertilizer to promote steady growth. When watering perennials, they should be watered less often (only once or twice a week), but deeply to encourage the roots to go down rather than out. Be sure to keep the bed dressed with a 3 inch layer of shredded wood mulch to curtail water evaporation and to choke out weeds. Shredded wood mulches also have the added benefit of decomposing over time, which puts more nutrients into the soil.

And while perennials do not need to be planted every year, for those that go dormant in the winter, you need to provide basic yearly maintenance. After a perennial has gone through one or two hard frosts, cut back the foliage to within 4-6 inches from the ground as this helps prevent the spread of diseases and cleans up the look of the bed. Every two or three years, perennials will also need to be divided and thinned out so that they do not become overgrown and stagnant.

With these basics under your belt, you are now ready to enter the realm of PERENNIALS!

TOP PERENNIALS FOR SUN

The following perennials were chosen for their heat and drought tolerance.

Angel’s Trumpet (Datura meteloides)  Height: 3-4 feet   Spread: 3-5 feet
Flower color: White   Bloom period: Spring to Fall  Herbaceous
Fragrant. Very hardy. Tolerant of poor soils. All parts of the plant are poisonous.  Other notable variety: Purple Petticoats

Autumn Sage (Salvia greggii)   Height: 2-3 feet   Spread: 18 inches- 2 feet
Flower color: Red   Bloom period: Spring to Fall Semi-evergreen
Attracts hummingbirds. Shear to keep bushy.  Other varieties: Hot Lips, Wild Thing, Ultra Violet, Furman’s Red, Coral

Balloon Flower (Platycodon grandiflorus)  Height: 8-10 inches   Spread: 9 inches
Flower Color: Blue, Pink, White  Bloom Period: Summer   Herbaceous
Large star-shaped blooms on compact plants. Plant in well-drained soil in full sun to part shade.

Black-eyed Susan (Rudbeckia hirta)  Height: 2-3 feet   Spread: 1-2 feet
Flower color: Yellow   Bloom period: Summer  Herbaceous
Butterfly nectar plant.  Short-lived perennial that reseeds and naturalizes easily. Makes a great cut flower. Deadhead to encourage new blooms.  Notable variety: Goldstrum

Blackfoot Daisy (Melampodium leucanthum) Height: 12-18 inches    Spread: 12-18 inches
Flower color: White     Bloom period: Summer to Fall Herbaceous

Blanket Flower (Gaillardia grandiflora) Height: 12-30 inches  Spread: 18 inches
Flower color: Yellow, orange, red Bloom period: Summer to Fall Herbaceous
Deadhead to encourage blooms. Tolerates poor soils.  Notable varieties: Gallo Yellow, Sun Devil, Goblin, Arizona Sun

Butterfly Bush (Buddleia davidii)  Height: 4-6 feet   Spread: 4-5 feet
Flower color: Purple, pink, white Bloom period: Summer to Fall Deciduous, shrub-like
Butterfly nectar plant. Grows quickly. Deadhead to encourage new blooms.  Notable varieties: Black Knight, Blue Chip, Miss Molly, Nanho Blue

Butterfly Weed (Asclepias tuberosa)  Height: 24-36 inches  Spread: 18-24 inches
Flower color: Orange   Bloom period: Summer to Fall Herbaceous
Butterfly nectar and host plant. Remove seed pods to encourage new blooms.

Coneflower (Echinacea purpurea)  Height: 2-4 feet    Spread: 18-24 inches
Flower color: All colors except blue Bloom period: Late Spring to Fall Herbaceous
Butterfly nectar plant. Long-lived perennial. A staple for any perennial garden and makes a great cut flower. Deadhead to encourage new blooms. Tolerant of poor soils.  Notable varieties: Magnus, Pow Wow

Coreopsis (Coreopsis grandiflora)  Height: 2-3 feet    Spread: 2 feet
Flower color: Yellow, pink, red  Bloom period: Late Spring to Early Summer  Herbaceous.
Butterfly nectar plant. Short-lived perennial that reseeds and naturalizes easily. Deadhead to encourage blooms. Tolerates poor soils.  Notable varieties: Crème Brulee, Early Sunrise, Heaven’s Gate, Jethro Tull, Moonbeam, Route 66, Salsa

Daylily, Stella de Oro (Hemerocallis x hybrida) Height: 24 inches  Spread: 18-24 inches
Flower color: Yellow    Bloom period: Summer  Herbaceous
Reblooms throughout the summer.  Other notable varieties: Ming Toy, Happy Returns

Dwarf Mexican Petunia (Ruellia brittoniana)  Height: 8 inches  Spread: 12 inches
Flower color: Purple, pink, white  Bloom period: Spring to Fall Evergreen
Low maintenance. Reseeds quickly. Great groundcover for the sun. Tolerant of poor soils.

Garden Phlox (Phlox paniculata)  Height: 18-30 inches   Spread: 18 inches
Flower color: Pink, lavender, white Bloom period: Late Spring-Summer Herbaceous
Butterfly nectar plant. Fragrant. Notable varieties: John Fanick, Victoria, Robert Poore, David

Gaura (Gaura lindheimeri)   Height: 18 inches   Spread: 18-30 inches
Flower color: White, pink  Bloom period: Summer to Fall  Herbaceous
Adds a soft movement to gardens. Notable varieties: Whirling Butterflies, Crimson Butterflies, Passionate Blush

Hardy Hibiscus, “Texas Star” (Hibiscus coccineus) Height: 6-8 feet   Spread: 3 feet
Flower color: Red    Bloom period: Summer  Herbaceous
Water and fertilize consistently.  Other notable varieties: Lady Baltimore, Lord Baltimore, Kopper King, Turn of the Century, Luna Pink Swirl, Luna Red, Luna White

Lamb’s Ear (Stachys byzantina)  Height: 12-18 inches   Spread: 24 inches
Flower color: Lavender   Bloom period: Spring   Evergreen
Very tough perennial. Soft to the touch. Removing blooms is encouraged.

Lantana, “New Gold” (Lantana x hybrida) Height: 12 inches   Spread: 24-36 inches
Flower color: Yellow   Bloom period: Late Spring to Fall Herbaceous
Butterfly nectar plant.  Other notable varieties: Dallas Red, Bandana series, Bandito series

Mealycup Sage, Victoria Blue (Salvia farinacea)  Height: 12 inches  Spread: 12 inches
Flower Color: Violet blue   Bloom Period: Spring-Fall  Herbaceous
Texas native with 8-10 inch flower spikes, attractive grayish-green foliage.  Other notable varieties: Evolution

Mexican Bush Sage (Salvia leucantha)  Height: 4 feet    Spread: 3 feet
Flower color: Purple, white  Bloom period: Summer to Fall  Semi-evergreen
Attracts hummingbirds. Silvery foliage complements other plants well. Notable variety: Santa Barbara

Pincushion Flower (Scabiosa caucasica) Height: 12 inches   Spread: 18 inches
Flower color: Purple, pink  Bloom period: Spring to Fall  Herbaceous
Butterfly nectar plant.  Makes a great cut flower.  Notable Varieties: Butterfly Blue, Pink Mist

Red Hot Poker (Kniphofia uvaria)  Height: 3-5 feet    Spread: 3 feet
Flower color: Yellow, orange, red Bloom period: Summer to Fall  Herbaceous
Attracts hummingbirds.  Notable varieties: Creamsicle, Ember Glow, Papaya Popsicle, Pineapple Popsicle

Russian Sage (Perovskia atriplicifolia)  Height: 3-4 feet    Spread: 3-4 feet
Flower color: Light purple/ light blue Bloom period: Summer to Fall  Deciduous
Long blooming period. Very hardy. Fragrant.

Salvia, Black and Blue (Salvia Guaranitica) Height:  30-40 inches    Spread: 24 inches
Flower Color: Electric Blue  Bloom Period: Mid-Summer  Herbaceous
Flowers contrast sharply with black stems in summer.  Butterflies and hummingbirds love them.

Salvia, Indigo Spires (Salvia x longispicata)  Height:  4 feet      Spread: 24 inches
Flower Color: Blue   Bloom Period: Summer-Fall  Herbaceous
Large 15 inch spike flowers.  Other notable varieties: Mystic Spires (dwarf) reaches height of 18-24 inches.

Salvia, May Night (Salvia nemorosa)   Height: 18-24 inches   Spread: 12 inches
Flower Color: Blue Violet  Bloom Period: Spring-Summer   Herbaceous
Butterflies and hummingbirds love it.

Santolina, Gray “Lavender Cotton” (Santolina chamaecyparissus)  Height:  12-18 inches  Spread: 2 feet
Color: Yellow    Bloom Period: Late Spring-Summer  Evergreen
Aromatic dense silver green foliage.  Loves heat.  Tolerates poor, dry soil.

Skullcap, Pink (Scutellaria suffrutescens)  Height:   8-12 inches    Spread: 2-3 feet
Flower Color: Pink   Bloom Period: Spring to Fall   Herbaceous
Hardy evergreen with small leaves stays low, spreads wide and blooms heavily all summer.

Texas Primrose (Calylophus drummondii)  Height:   8-12 inches    Spread: 2 feet
Flower Color: Yellow   Bloom Period: Spring to Fall   Herbaceous
Bushy and upright growth habit and needle-like foliage. Tolerates poor, dry soils.

Turk’s Cap (Malvariscus arboreus)  Height: 4-5 feet    Spread: 4 feet
Flower color: Red   Bloom period: Spring to Fall  Deciduous
Shrub-like perennial. Attracts hummingbirds. Can be planted in full sun to full shade.
Tuscan Blue Rosemary (Rosmarinus officinalis) Height: 3-4 feet    Spread: 2-3 feet
Flower color: Light purple/ light blue  Bloom period: Spring to Summer Evergreen shrub
Culinary uses. Be careful not to overwater. Other notable varieties: Hardy, Prostrate

Veronica “Royal Candles Speedwell” (Veronica spicata) Height: 12 inches  Spread: 12 inches
Flower color: Violet Blue   Bloom period: Summer to Fall  Herbaceous
Upright, compact. Great for decorative containers, low borders or mass plantings.

Wormwood, “Powis Castle” (Artemisia ludoviciana)  Height: 3 feet   Spread: 2-3 feet
Foliage color: Silver/grey
Be careful not to over water. Complements other plants well with its neutral colored, soft textured foliage. Tolerates poor soils. Other notable variety: Silver Mound (dwarf) reaches 9 inches tall and 24 inches wide.

Yarrow (Achillea millefolium)    Height: 2-3 feet    Spread: 2-3 feet
Flower color: White, peach, pink, orange, red Bloom period: Late Spring to Fall Herbaceous
Butterfly nectar plant. Tolerates poor soils. Notable varieties: Moonshine, Paprika, Summer Pastels

TOP PERENNIALS FOR SHADE
The following perennials were chosen for their heat tolerance.

Ajuga (Bugleweed)     Height: 6-10 inches    Spread: 12-24 inches
Flower Color: Blue   Bloom Period: Spring
Foliage Color: Pale burgundy, green, black, bronze    Herbaceous
Rapid growing, easy to maintain evergreen groundcover. Grows well under trees & where other plants have difficulty.  Notable varieties: Black Scallop, Bronze Beauty, Burgundy Glow, Chocolate Chip, Catlin’s Giant

Autumn Fern (Dryopteris erythrosora) Height: 18 inches – 2 feet  Spread: 18 inches
Foliage color: Green in the Summer; orange in the Fall.    Herbaceous  Drought tolerant
Will provide interest to your garden all year long.  Cut back damaged fronds after new growth begins in spring.

Columbine (Aquilegia chrysantha)   Height: 2 feet   Spread: 2 feet
Flower color: White, yellow, blue, red  Bloom period: Spring  Herbaceous
Butterfly nectar plant. Long-lived and reseeds freely.  Notable varieties: Texas Gold, Origami

Coral Bells (Heuchera)    Height: 12-18 inches  Spread: 12-18 inches
Foliage color: Purple, red, green, silver, black, brown, orange
Flower color: Pink, red, cream, white  Bloom period: Spring  Evergreen
Butterfly nectar plant. Attracts hummingbirds. Some varieties are fairly sun tolerant when given enough water.  Notable varieties: Cinnabar Silver, Stoplight, Paprika, Shanghai, Delta Dawn, Fire Alarm, Lime Marmalade, Sweet Tart

Dead Nettle (Lamium maculatum)  Height: 6-8 inches   Spread: 2-3 feet
Flower color: Pink, white  Bloom period: Late Spring to Early Summer  Herbaceous
Adds highlights to shady areas. Drought tolerant. Notable varieties: Pink Pewter, White Nancy, Beacon Silver

Fescue, “Elijah Blue” (Festuca glauca) Height: 8-12 inches   Spread: 8-12 inches
Flower color: Tan   Bloom period: Late Summer  Evergreen
Grows quickly. Drought tolerant. Great as a ground cover or edging.

Foxglove (Digitalis purpurea)   Height: 2-5 feet    Spread: 12-30 inches
Flower color: Pink, purple, white Bloom period: Spring to Summer Herbaceous
Biennial that reseeds easily. Attracts hummingbirds. All parts of this plant are poisonous.

Foxtail Fern (Asparagus Meyeri)  Height: 2 feet    Spread: 3-4 feet
Flower color: White   Bloom period: Summer   Evergreen
Not a true fern. Fairly sun tolerant when given enough water.

Holly Fern (Cyrtomium falcatum)  Height: 2-3 feet    Spread: 3 feet Evergreen
Large, glossy dark green fronds. Unique look among ferns. Somewhat drought tolerant.
Hosta (Plantain Lily)    Height: 1-5 feet   Spread: 1-5 feet (Depending on variety)
Flower color: White, lilac, purple Bloom period: Summer  Herbaceous
Versatile, use for borders to centerpieces.  Notable varieties: Patriot, Stained Glass, Guacamole, Blue Angel

Lenten Rose (Helleborus orientalis)  Height: 12-18 inches  Spread: 2-3 feet
Flower color: White, pink, purple Bloom period: Late Winter to early Spring Evergreen
Long blooming period. Makes an attractive ground cover. Drought tolerant.  Notable varieties: Golden Lotus, Pink Frost, Harlequin Gem, Honeyhill Joy

Lily of the Nile, “Peter Pan” (Agapanthus)  Height: 12-18 inches  Spread: 18 inches
Flower color: Light blue   Bloom period: Spring to Early Summer  Evergreen
Dwarf variety.  Other notable varieties: Lily of the Nile (the original), White Lily of the Nile

Oxalis, Purple Shamrock, Triangularis (Oxalis regnellii)  Height: 10-12 inches   Spread: 12 inches
Flower Color: Lilac     Bloom Period: Spring to Fall
Purple leaflets shaped like triangles in groups of three. Holds purple color well in shade. Mulch in winter.

Variegated Flax Lily (Dianella tasmanica ‘Variegata’) Height: 3 feet   Spread: 1 foot
Flower color: White     Bloom period: Summer  Evergreen
Adds highlights to shady gardens.  Other notable variety: Indigo Bells, Cassa Blue
Revised 6/22/15