Common periwinkle

Year-round

Common periwinkle is a low, trailing evergreen groundcover from Europe that you already have in your garden. In Georgia it is listed as a moderate invasive plant problem, so the goal is managing and containing what you have rather than letting it spread.

• Keep it inside a defined bed edge, trailing stems root wherever they touch soil and can creep well past where you planted it
• Edge or trim the perimeter regularly so it does not cross into lawn, mulch beds, or nearby wooded or natural areas
• Never dump pulled clippings in a natural area or compost pile that touches open ground, rooted stems can start new patches
• If you have dogs or cats that spend time in this bed, know that vinca contains vinca alkaloids and is listed as toxic to dogs, cats, and horses
• Bag and trash (not compost near a natural edge) any large volume of trimmings removed during containment work

A well-edged periwinkle bed reads as tidy and HOA-friendly groundcover, but an unchecked patch spreading past its border can look unkempt and is worth keeping trimmed back.

Fall

Fall is a good window for a thorough containment pass in Atlanta, before the first frost in mid-November slows growth for the year.

• Rake fallen leaves off the groundcover so it does not mat down and hold moisture against the foliage
• Do one more edging pass to catch runners that spread during the growing season
• Fall is also fine timing for dividing or relocating a small patch if you want it in a more contained spot
• Dispose of any removed runners in the trash, not a curbside yard-waste pile that could re-root

Winter

This groundcover stays evergreen through Atlanta's mild winters, so it needs little upkeep, but it is a low-effort time to do one more check for stray runners.

• No winter protection is needed, it holds up fine through Atlanta's zone 7b/8a winters
• A slow season is a good time to walk the bed edge and pull any runners that have escaped since fall
• If dogs or cats have outdoor access to this bed, keep in mind vinca is listed as toxic to dogs, cats, and horses
• Skip fertilizing, this plant does not need extra encouragement to grow

Spring

Spring brings a flush of new growth and small blue-violet flowers, and it is the best time of year in Atlanta to get ahead of this plant's spreading habit before summer growth takes off.

• After Atlanta's last frost in late March, trim back runners that crept past the bed edge over winter
• Check for stems that have rooted into the lawn or adjacent beds and pull those before they establish
• A light spring feeding is not necessary, this groundcover grows vigorously on its own
• Good time to install a physical edge (metal or plastic edging, a mowed strip) if the bed does not already have one

Summer

Atlanta's hot, humid summers are exactly the conditions this groundcover thrives in, which means containment work needs to happen more often, not less.

• Trim the perimeter every few weeks during peak summer growth to keep it from creeping into lawn or nearby beds
• Watch for leaf spot in prolonged humid, wet stretches, thin dense patches for better airflow if you see spotting
• Water is rarely needed once established, this plant tolerates Georgia's summer heat well on its own
• Avoid letting mowed or trimmed stems sit in a pile touching bare soil near a wooded edge, they can root there

Year-round

Lesser periwinkle is a low, trailing evergreen groundcover that spreads by rooting stems; in the Houston area it does best in shaded to part-shade beds where summer heat is less intense.

• Plant in part shade to full shade; Houston's hot, humid summer sun can scorch the foliage.
• Water regularly through the first growing season to establish; once rooted it tolerates dry spells.
• Shear or mow lightly once a year to keep growth dense and manage its spread.
• Reported toxic to dogs, cats, and horses if ingested, per the ASPCA, so keep pets that chew on foliage away from the bed.

Kept edged and mowed low, it reads as a tidy shaded groundcover rather than an unmanaged spread, which keeps it HOA-friendly.

Fall

Growth slows as temperatures cool; fall is a good window for a light trim and new plantings.

• Cooler, milder fall weather is a good window for planting new periwinkle divisions.
• Reduce watering as the weather cools and rainfall picks up.
• Clear fallen leaves off the bed so they don't smother the low foliage.

Winter

In the Houston area periwinkle stays evergreen through winter with only occasional frost damage during hard freezes.

• Foliage may brown after a hard freeze but typically resprouts as temperatures warm.
• Hold off on major pruning until freeze risk has passed for the season.
• Keep the bed on the drier side while growth is slow through winter.

A frost-browned patch can look ragged; a light shearing once freeze risk passes restores a tidy appearance.

Spring

Spring is bloom season and a good time to tidy up winter-tattered foliage and expand plantings.

• Shear back any winter-tattered foliage in late winter to early spring to make room for fresh growth.
• Watch for violet-blue flowers appearing through the foliage in March and April.
• Divide and replant crowded sections if you want to expand coverage elsewhere in the bed.

Summer

Houston's summer heat and humidity are the toughest stretch for periwinkle; consistent shade and moisture keep it from scorching.

• Water during dry stretches, especially in beds that get any afternoon sun.
• Watch for fungal leaf spot in humid weather; thin dense mats to improve airflow if it appears.
• Keep it edged back from walkways and turf so it doesn't spread past the bed.