It is thought to be a hybrid between two South African species (P. opposistifoliaandP.
myrtifolia) and is sometimes known asPolygala myrtifolia grandiflora.
It is normally planted in the spring after the soil has fully warmed.
Sweet pea shrub is most commonly planted in the spring from potted nursery plants.
Water regularly as the plant is becoming established, and feed it every spring.
Light
Full sun or lightly dappled positions are best for the sweet pea shrub.
This will ensure it flowers abundantly.
If it gets too much shade, sweet pea shrub can become overly leggy with few blossoms.
It doesn’t appreciate overly wet and heavy soil.
A slightly acidic pH is preferable, though sweet pea shrub will also tolerate neutral soil.
Give it about one inch of water each week, unless your garden has received ample rainfall.
Once established, sweet pea shrub is surprisingly tolerant of short droughts, up to two or three weeks.
But extended droughts that completely dry out the plant’s roots can be deadly.
It’s a good idea to addmulcharound the base of the plant once it has been established.
This will help it to retain moisture during infrequent watering.
Mulching will also help protect the shrub when the winter temperatures arrive.
But this plant doe not like prolonged chilly, damp conditions.
Fertilizer
Using a balanced slow-release fertilizer in the spring can encourage strong blooming.
In regions with especially long blooming periods, a second feeding in the fall is often helpful.
Container plants may require monthly light feeding.
Types of Sweet Pea Shrub
There are no commonly sold named cultivars of sweet pea shrub.
However, there is a related plant,Polygala fruticosa,which is often mistaken forP.
fruticosagoes by the common name dwarf sweet pea shrub.
Because it is more compact, dwarf sweet pea shrub is a better choice for growing in containers.
Annual pruning to eliminate sparsely blooming lower stems will encourage more abundant flowering.
To avoid sacrificing blooms, do your pruning after the main flowering periods have concluded.
However, there is a similar speciesP.
fruticosa(dwarf sweet pea shrub)can be readily propagated by seed under the right conditions.
you’re free to start seeds indoors in small pots or seed trays filled with potting mix.
Plant the seeds so they are barely covered, about 1/16 inch deep.
Keep the potting mix moist, but not wet, during the germination period.
The plant is amenable to hard pruning, which allows it to remain a nicely trained container plant.
Ordinary commercial potting soil works well as a growing medium for containers.
Use the largest pot that is practical, which will limit how often you must repot.
ensure the container drains well.
Watering and feeding must be done more frequently with container-grown shrubs.
In winter, your container sweet pea shrub should be moved into a sheltered outdoor location.
In colder climates, these plants may need to be sheltered against cold winter winds to survive.
And regular hard pruning will keep the plant dense and full of flowers.
In zones where the plant blooms into fall, a second feeding is recommended.
Leaves Are Yellow
Yellowing leaves are a symptom of too much water.
Don’t irrigate this plant in weeks when your garden has received rainfall.
Before watering again, confirm the top 2 inches of soil are dry to the touch.
The sweet pea shrub develops into a rounded mound with a loose, relaxed appearance.
It is a common plant in cottage gardens and rock gardens.
It can also be massed for use in shrub borders or foundation plantings.
Sweet pea shrub eagerly accepts hard pruning, making it useful for informal hedges.
Potted sweet pea plants are also attractive in courtyards and patio gardens.
Thus, homeowners sometimes remove still-living mature plants because they are no longer attractive in the landscape.
This plant is not known as a butterfly magnet, but it is attractive to pollinating bees.
Avoid the use of pesticides if you want to be a bee-friendly gardener.
The thickest, woodiest stems should be removed entirely.
