Gregg Dalea

Year-round

Trailing indigo bush (Dalea greggii) is a low mounding, low water groundcover popular in Dallas-Fort Worth yards for slopes, hot parking strips, and xeriscape beds. It comes from the Trans-Pecos region of far West Texas, not from North Texas, so the trade off for its drought tolerance is that it needs excellent drainage to handle DFW's clay soils and humid summers.

• Give it full sun, at least six hours a day, for the tightest mounded form and best bloom.
• Good drainage matters more than anything else here. In Fort Worth's sandier Cross Timbers soils that usually just means avoiding low spots, in Dallas's heavier Blackland clay it often means planting on a slope or mounding the bed and mixing in expanded shale or coarse sand.
• Once established, water deeply about once a week in hot weather and let the soil dry out between waterings. Overwatering, not underwatering, is the most common way this plant fails here.
• It spreads four to six feet wide and mounds twelve to eighteen inches tall, so give it eight to ten feet of open bed. It is not a good fit for small planting strips.
• Its purple flower spikes draw bees and butterflies, and it serves as a larval host plant for several butterfly species.

Fall

Fall in DFW means cooling temperatures through the average first freeze around November 22, and trailing indigo bush should be winding down growth by then, not putting out new growth.

• Cut back on watering as temperatures drop. The plant needs much less water once daytime highs fall out of the 90s.
• Do not shear or prune in fall. New growth stimulated this late does not harden off before frost and is usually what gets damaged first.
• Fall is also a good planting window in DFW, since cooler air and still warm soil help new roots establish before winter.
• Check that the mound has good airflow against the soil. Wet foliage sitting on heavy clay through fall is a common source of crown rot.

Leaving the mound unpruned through fall keeps its shape and silhouette intact for the front yard. Save any shaping for spring.

Winter

Winters in DFW are generally mild but bring occasional hard freezes. Trailing indigo bush is evergreen in a typical winter and can die back or brown after a harder one.

• Hold off on pruning any winter damaged or browned stems until spring, once new growth low on the plant shows you what is actually alive. Cutting too early risks removing live wood.
• Water sparingly in winter, only during extended dry spells. Wet clay soil combined with a hard freeze raises the risk of root rot.
• If a hard freeze or ice event is forecast, a light frost cloth over the mound gives extra protection, since this plant is grown well outside its native West Texas range here.
• A harder freeze can leave the mound looking brown and ragged. That is usually cosmetic, and it typically resprouts from the base in spring.

A browned mound after a freeze can look neglected from the street. It is normal winter dieback here and usually fills back in by late spring, not a sign to remove the plant.

Spring

Spring, after DFW's average last freeze around March 12, is when trailing indigo bush pushes new growth and starts its main bloom flush.

• Wait until you see new growth low on the stems before judging winter damage, then trim back any dead or bare wood.
• If the mound needs shaping, do it now with a light shearing before new growth hardens off. It blooms on new growth, so avoid heavy pruning later in the season.
• Purple flower spikes typically begin in April and run into early summer, drawing in bees and butterflies.
• Spring is a good window to plant new specimens, since roots get a full growing season to establish before summer heat arrives. Wait until frost risk has passed, and mix in expanded shale or sand at planting time if you are in Dallas's heavier clay.

A light spring shearing keeps the mound tidy and low along a front walk or slope, which reads as tended rather than overgrown.

Summer

Summer is peak bloom and peak heat tolerance for this plant. Established trailing indigo bush handles DFW's hot, humid July and August well once it is settled in.

• Water deeply about once every seven to ten days during hot stretches, and skip watering after a heavy rain.
• Established plants tolerate full sun and reflected heat from streets, driveways, or south facing walls.
• Yellowing or wilting after a heavy summer rain usually points to standing water in heavy clay, not heat stress. Check drainage before adding more water.
• Deadheading spent flower spikes is optional. It keeps the bed looking neat but does not change how much the plant reblooms.
• Skip the fertilizer. Extra feeding pushes soft growth that struggles in DFW's summer heat and humidity.

Year-round

Trailing indigo bush (Dalea greggii) is a low mounding, low water groundcover popular in Dallas-Fort Worth yards for slopes, hot parking strips, and xeriscape beds. It comes from the Trans-Pecos region of far West Texas, not from North Texas, so the trade off for its drought tolerance is that it needs excellent drainage to handle DFW's clay soils and humid summers.

• Give it full sun, at least six hours a day, for the tightest mounded form and best bloom.
• Good drainage matters more than anything else here. In Fort Worth's sandier Cross Timbers soils that usually just means avoiding low spots, in Dallas's heavier Blackland clay it often means planting on a slope or mounding the bed and mixing in expanded shale or coarse sand.
• Once established, water deeply about once a week in hot weather and let the soil dry out between waterings. Overwatering, not underwatering, is the most common way this plant fails here.
• It spreads four to six feet wide and mounds twelve to eighteen inches tall, so give it eight to ten feet of open bed. It is not a good fit for small planting strips.
• Its purple flower spikes draw bees and butterflies, and it serves as a larval host plant for several butterfly species.

Fall

Fall in DFW means cooling temperatures through the average first freeze around November 22, and trailing indigo bush should be winding down growth by then, not putting out new growth.

• Cut back on watering as temperatures drop. The plant needs much less water once daytime highs fall out of the 90s.
• Do not shear or prune in fall. New growth stimulated this late does not harden off before frost and is usually what gets damaged first.
• Fall is also a good planting window in DFW, since cooler air and still warm soil help new roots establish before winter.
• Check that the mound has good airflow against the soil. Wet foliage sitting on heavy clay through fall is a common source of crown rot.

Leaving the mound unpruned through fall keeps its shape and silhouette intact for the front yard. Save any shaping for spring.

Winter

Winters in DFW are generally mild but bring occasional hard freezes. Trailing indigo bush is evergreen in a typical winter and can die back or brown after a harder one.

• Hold off on pruning any winter damaged or browned stems until spring, once new growth low on the plant shows you what is actually alive. Cutting too early risks removing live wood.
• Water sparingly in winter, only during extended dry spells. Wet clay soil combined with a hard freeze raises the risk of root rot.
• If a hard freeze or ice event is forecast, a light frost cloth over the mound gives extra protection, since this plant is grown well outside its native West Texas range here.
• A harder freeze can leave the mound looking brown and ragged. That is usually cosmetic, and it typically resprouts from the base in spring.

A browned mound after a freeze can look neglected from the street. It is normal winter dieback here and usually fills back in by late spring, not a sign to remove the plant.

Spring

Spring, after DFW's average last freeze around March 12, is when trailing indigo bush pushes new growth and starts its main bloom flush.

• Wait until you see new growth low on the stems before judging winter damage, then trim back any dead or bare wood.
• If the mound needs shaping, do it now with a light shearing before new growth hardens off. It blooms on new growth, so avoid heavy pruning later in the season.
• Purple flower spikes typically begin in April and run into early summer, drawing in bees and butterflies.
• Spring is a good window to plant new specimens, since roots get a full growing season to establish before summer heat arrives. Wait until frost risk has passed, and mix in expanded shale or sand at planting time if you are in Dallas's heavier clay.

A light spring shearing keeps the mound tidy and low along a front walk or slope, which reads as tended rather than overgrown.

Summer

Summer is peak bloom and peak heat tolerance for this plant. Established trailing indigo bush handles DFW's hot, humid July and August well once it is settled in.

• Water deeply about once every seven to ten days during hot stretches, and skip watering after a heavy rain.
• Established plants tolerate full sun and reflected heat from streets, driveways, or south facing walls.
• Yellowing or wilting after a heavy summer rain usually points to standing water in heavy clay, not heat stress. Check drainage before adding more water.
• Deadheading spent flower spikes is optional. It keeps the bed looking neat but does not change how much the plant reblooms.
• Skip the fertilizer. Extra feeding pushes soft growth that struggles in DFW's summer heat and humidity.