Groundcover
Trailing periwinkle (vinca groundcover)
Vinca major · Apocynaceae
Also called: Bigleaf periwinkle, Greater periwinkle, Vinca, Trailing vinca
Trailing periwinkle (vinca groundcover) (Vinca major) is a moderate-water groundcover well suited to Tucson and the low desert.
Trailing periwinkle (vinca groundcover) at a glance
- Water use
- Moderate (established)
- Sun
- Partial to full shade in Tucson; requires afternoon shade. Full low-desert/reflected sun scorches and bleaches the foliage. Best on north/east exposures and under trees
- Mature size
- 6-18 in tall, spreading indefinitely by rooting runners; mounds and cascades over edges and walls
- Growth rate
- Fast/aggressive; trailing stems root at the nodes (tips) and spread rapidly to form a dense mat
- Bloom
- Lavender-blue to violet pinwheel/star flowers, Spring (peak), with scattered bloom into summer/fall in shade with adequate water
- Cold hardiness
- Evergreen; hardy in 9a-9b. May suffer minor frost burn on foliage in cold snaps but recovers vigorously in spring. Hardy well below Tucson's winter lows
- Soil
- Very adaptable; tolerates Tucson's alkaline and clay soils. Performs best in soil improved with organic matter and kept moist; not fussy about fertility
- Native range
- Mediterranean region and southern Europe; introduced and invasive in many parts of North America (including riparian areas of the West)
- Best used as
- Shaded groundcover, Slope/bank cover and erosion control, Cascading over walls and planters, Understory cover beneath trees and shrubs
- Wildlife
- Some pollinator value from spring flowers; deer-resistant due to toxic alkaloids
- Toxicity
- Toxic — in the dogbane family (Apocynaceae); contains vinca alkaloids. Considered toxic if ingested by pets, livestock, and humans, and the sap can irritate skin. Keep away from pets and children
How to grow Trailing periwinkle (vinca groundcover) in Tucson & the low desert
Watering
Water regularly to keep soil moist — deeply 1-2 times per week in summer heat and every 10-14 days in cooler months. It wilts and browns quickly when dry in the heat and is not drought-adapted for the low desert; consistent moisture and mulch are needed. Moderate water use.
Fertilizer & nutrients
Light feeder: a balanced or slow-release fertilizer in spring is sufficient; over-feeding accelerates its already-aggressive spread. Chelated iron corrects chlorosis in Tucson's alkaline soils. Organic mulch improves vigor and moisture retention.
Pruning & care
Shear or mow back hard in late winter/early spring to renew the planting and remove leggy or frost-burned growth; cut back runners through the season to contain spread. Responds well to hard renewal pruning.
Notes
A vigorous, fast-spreading evergreen groundcover for SHADE in Tucson — it must have afternoon shade and regular water and will scorch in full reflected sun. Aggressive: its rooting runners escape beds readily and Vinca major is listed as invasive in riparian/natural areas across the West, so install with a hard edge or in contained beds and avoid planting near washes or natural desert. Best used in shaded courtyards, under trees, on north/east slopes, and spilling over walls. Distinct from the smaller, less-aggressive Vinca minor and from the unrelated annual bedding 'vinca' (Catharanthus roseus).
Sources: University of Arizona / Pima County Cooperative Extension (groundcovers for the low desert); AMWUA Landscape Plants for the Arizona Desert; California Invasive Plant Council (Cal-IPC) — Vinca major invasiveness; North Carolina Extension Gardener Plant Toolbox (Vinca major)