The Story
Plant Bio
Polygala myrtifolia, the myrtle-leaf milkwort, is an upright, rounded evergreen shrub native to South Africa that reaches five to ten feet in height and width. The dense foliage consists of small, narrow, deep green leaves with a slightly leathery texture, resembling myrtle.
The vivid purple to magenta, pea-like flowers feature a prominent fringed or tufted keel crest and appear in terminal clusters at the tips of new growth. Flowering peaks in spring and fall, with scattered blooms continuing through mild winters.
Uses & Benefits:
Essentials
At a Glance
Plant Type
Shrub
Height
118"
Width
118"
Light
Full Sun, Partial Sun
Zones
9, 10
Water
Low
Humidity
Moderate to High
Lifespan
10-20 years
Native To
South Africa
Toxicity
Non-toxic
Bloom period
Spring – Fall
In flower about 9 months of the year
Planting
How to Grow
- Select a planting site in full sun to light shade with exceptionally well-drained, sandy or light soil.
- Dig a hole twice as wide as the root ball and of equal depth, ensuring the crown sits level with the surrounding soil.
- Water deeply immediately after planting to settle the soil, then establish a moderate watering schedule until the root system is established.
- Apply a light layer of organic mulch around the base to retain moisture, keeping the mulch clear of the main stem.
Pro Tip
Pruning past the green, leafy zone into bare brown stems kills the branch permanently because this species lacks latent buds on old wood.
Keep It Thriving
Care Guide
Do
- Prune lightly immediately after major flowering flushes to maintain a dense, bushy shape.
- Ensure the soil drains rapidly, as waterlogged conditions trigger fatal root rot.
- Provide full sun exposure to maximize the density of the foliage and the abundance of flowers.
Don't
- Do not cut back into old, leafless woody stems, as the plant cannot regenerate from old wood.
- Do not overwater or plant in heavy, poorly aerated clay soils.
- Do not apply heavy doses of fertilizer, as this species has low nutrient requirements.
Seasonal Care Calendar
| Task | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Fertilize | ||||||||||||
| Mulch | ||||||||||||
| Pest Check | ||||||||||||
| Prune |
Watch Out For
Pests & Diseases
Common Pests
Common Diseases
In the Garden
Landscape Uses & Companions
Landscape Uses
Companion Plants
Multiply
Propagation Methods
Good to Know
Common Questions
Myrtle-Leaf Milkwort questions
What zones can Myrtle-Leaf Milkwort grow in?
Myrtle-Leaf Milkwort is hardy in USDA Zones 9–10. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.
Is Myrtle-Leaf Milkwort deer resistant?
Not reliably. Deer may browse Myrtle-Leaf Milkwort, especially tender spring growth — plan on repellents or fencing where pressure is high.
When does Myrtle-Leaf Milkwort bloom?
Myrtle-Leaf Milkwort typically blooms in spring through fall. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.
Does Myrtle-Leaf Milkwort need full sun?
Myrtle-Leaf Milkwort does best in full sun to part shade. In hot climates, afternoon shade keeps blooms fresher longer.
Is Myrtle-Leaf Milkwort drought tolerant?
Yes — once established (usually after the first full season), Myrtle-Leaf Milkwort handles dry spells with minimal watering. Water deeply its first year to build the root system that makes that possible.
Keep exploring
Explore the genus
Hardy in your zone?
Grow Myrtle-Leaf Milkwort with confidence
See it in a design of your actual yard, get zone-matched care reminders, and track it season by season in your garden journal.