Ornamental · Plantaginaceae
Angelonia
Angelonia angustifolia
Give it full sun and heat, and angelonia raises slim spires studded with lipped flowers from summer to fall.
Full sun
USDA 9–11
12–18 in · 30–46 cm
Overview
Angelonia, the summer snapdragon, carries its flowers on slim upright spires that climb through the heat of the season. Each spire opens a run of small lipped blooms in purple, pink, white, or blue, holding them from early summer into fall. The flower wears the curved, pouched look of a snapdragon, yet the plant sits in the family Plantaginaceae and shares no kinship with one.
The plant grows as a rounded, leafy mound about 12 to 18 inches (30 to 46 cm) tall, its narrow toothed leaves stacked close along upright stems. It is hardy only in zones 9 to 11, so most gardeners grow it as a warm season annual and set in fresh plants each spring. Sun and warmth are what coax the densest, most flower-laden form from it.
Up close the appeal is in the detail. The foliage is slim and a little tacky to the touch, the stems stand stiff and erect, and the open flowers crowd the upper third of each spire. Once the roots have a grip it shrugs off drought and humidity, sheds its old blooms on its own, and rarely shows pest damage, so the spires stay clean and full through the season.
Care
The short version: full sun, warmth, and soil that drains well keep the spires dense and flowering. Water it while the roots take hold, then let it dry between drinks once established, and shear it back by half at midsummer if the spires start to thin.
Light
Angelonia wants full sun and as much of it as the day offers. The more direct light reaches the stems, the denser and stiffer the plant grows and the more thickly the spires flower, while shade leaves it thin, leaning, and sparse with bloom.
Water
Keep the soil evenly moist while the plant is rooting in, then ease off once the roots take hold. After that the slightly tacky foliage holds up well through dry spells and the soil can dry between waterings, as long as the drainage stays sharp. Soggy ground is the one thing the roots will not forgive.
Soil
Set it in moist, fertile soil that drains freely. Rich ground feeds the long succession of spires, but standing water rots the roots, so loosen heavy soil with compost and give the water a clear way out.
Humidity
Heat and damp air leave angelonia untroubled, so there is no number to chase. Airflow around the leaves is what counts, since still, muggy air pressed between crowded stems is what lets a powdery film take hold.
Feeding
Work a slow-release landscape fertilizer into the soil at planting and refresh it about every two months through the growing season. Where the soil is lean, an occasional liquid feed keeps the spires opening fresh flowers.
Pruning
No deadheading is needed, since the plant drops its faded flowers on its own. If the stems stretch and the spires thin by midsummer, shear them back by about half and fresh bloom returns within 2 to 3 weeks.
Size & spacing
Each plant stands 12 to 18 inches (30 to 46 cm) tall and spreads 8 to 12 inches (20 to 30 cm) wide. Leave that much gap between the mounds so air moves freely past the leaves and the powdery film stays off.
When to plant
Angelonia runs on warmth and will not stand frost. Start seed indoors in late winter, set the young plants out once the cold has truly passed and the soil has warmed, and the flower spires keep coming from early summer through the first chill of fall.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: Start seed indoors about 6 to 8 weeks before the last spring frost; seed needs light to germinate and sprouts in 7 to 14 days.
- Plant: Transplant outdoors after the last frost when soil and air have warmed.
- Harvest: Blooms from late spring or early summer through early fall (about June to September); allow roughly 13 to 14 weeks from sowing to flower.
Hardiness
USDA hardiness zones: 9–11
Temperature: down to -7°C
Troubleshooting
Angelonia is one of the more trouble-free annuals to grow, and most of the damage you will see on the leaves or stems traces back to soggy soil or stagnant air. The few signs below are worth learning so you can read the plant early. Match what shows on the foliage, then act while it still helps.
Stems sagging limp above soil that stays wet
A plant that goes slack while the soil around it sits soggy is showing Phytophthora root and stem rot, a water mold that takes over ground that never drains. The roots and the base of the stem turn brown and soft to the touch, and a plant rotted that deep cannot come back. Lifting and binning the worst ones, easing far back on water, and replanting where the soil drains sharp is the way through.
Fix:
- Remove and discard severely affected plants
- Improve drainage and reduce watering frequency
A pale powdery bloom dulling the leaves and stems
That chalky gray-white film clouding the leaf surface is powdery mildew, a fungus that creeps over leaves left damp in still air. Watering at the base keeps the foliage dry, thinning crowded growth lets the breeze slip between stems, and the most coated leaves come away. A plant standing in full sun with open space around it shows little of the dusty film.
Fix:
- Improve air circulation by spacing plants properly
- Avoid wetting foliage and water at the base
- Remove badly affected foliage
Tender tips kinking under clusters of small insects
Those soft pinhead specks massed on the curling new tips are aphids, and the glossy stickiness coating the growth around them is honeydew. A sharp jet of water sends most of them flying, and insecticidal soap clears the clingers when the colony grows thick. Lady beetles and their kin pick off the rest, so a lighter hand with nitrogen leaves fewer of the soft shoots that lure them.
Fix:
- Dislodge aphids with a strong spray of water
- Apply insecticidal soap if populations are high
- Encourage natural predators such as lady beetles
Toxicity
Good news for households with pets and children: angelonia is not listed as toxic. The ASPCA leaves it off its cat and dog lists, and there are no known poisons in the leaves or flowers. A curious nibble might upset a sensitive stomach the way any strange plant can, but the plant itself is safe.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Angelonia never made the ASPCA's toxic list, so a cat that bites into a leaf has nothing to fear from it.
Dogs None
Dogs are clear of it as well. A full mouthful of the leaves might unsettle a sensitive stomach the way any strange plant can, but no known toxin sits in the tissue.
Horses Safe
Nothing in angelonia is known to harm horses, so a grazed mouthful of the foliage poses no worry.
Rabbits Safe
Rabbits can crop the soft leaves and flowers without harm, though a hungry one may gnaw a young plant back to the bare stem.
Livestock Safe
Cattle, goats, and sheep meet no known toxic risk from angelonia growing in the pasture or border.
Birds Safe
Birds that peck at the leaves or the spent blooms take no harm from them.
People Safe
Angelonia is raised for the look of its flowers, not the table, but it holds no toxin, so a child who tastes a bloom comes to no harm.
Varieties
Angelonia comes in seed-grown series and vegetative ones, the latter bred for bigger flowers and held true by cuttings. A few names turn up again and again on the bench, each with its own cast of flower colors.
Serena and Serenita series
These compact, seed-grown plants bloom in purple, lavender pink, and clear white.
Archangel series
Grown from cuttings, these bear noticeably larger flowers in shades like blue and pink.
Night Sky
Its deep purple petals are freckled all over with small white dots.
How to propagate
You can multiply angelonia from cuttings or from seed, and the choice comes down to how much time you have and whether you want the exact flower color of a favorite copied true.
Stem cuttingsEasy
During active growth in the warm season. · A few weeks to root and establish.
A snipped tip is the fastest path to copy a plant whose color you like. Cut it while the stems are growing hard in the warm season, sink it into a moist medium, and fresh roots form and settle in within a few weeks. The named vegetative series are kept true to their exact flower color this same way.
SeedEasy
Start indoors 6 to 8 weeks before the last frost. · Germinates in 7 to 14 days with light; about 13 to 14 weeks from sowing to flower.
Seed takes patience but fills a flat with seedlings. Sow indoors 6 to 8 weeks before the last frost and leave the fine seed sitting bare on the surface, since light triggers it, and green shoots break through in 7 to 14 days. From that sowing to the first open flower runs roughly 13 to 14 weeks.
Myths
Angelonia needs constant deadheading to keep blooming.
Angelonia drops its spent flowers on its own and keeps blooming with no deadheading at all. If the spires thin and tire by midsummer, a single shearing by half refreshes the bloom within 2 to 3 weeks.
Angelonia is a true snapdragon.
The name summer snapdragon traces only to the lipped shape of the flower, not to any shared family. It is Angelonia angustifolia in the family Plantaginaceae, with no kinship to the true snapdragon, Antirrhinum.