HouseplantclimberSome care needed

Hoya

Hoya carnosa

A waxy-leaved epiphytic climber grown for clusters of scented flowers that appear only on mature plants in good light. The flower spurs are perennial and produce again from the same point, so cutting off the old flower stalk removes next year's flowers.

Position: Bright, out of direct sun
Water: low demand
Drainage: Free-draining
Grows to: 100–300 cm × 40–80 cm
Frost: Frost tender
Difficulty: Some care needed

Described view

A hoya flower cluster beside the bare perennial spur left after the previous year's flowers

August

Nothing to do

No sowing, planting, harvesting or pruning window falls in August.

Hoya’s year

Resolved for United Kingdom (general). Every window is stored against a climate event rather than a date, so a late frost pocket runs later than the band shows. What else August calls for.

Activity	J	F	M	A	M	J	J	A	S	O	N	D
Take cuttings					May.	June.	July.

Timing that travels

The band above resolves this plant's windows into months for one region. These are the windows themselves, stored against a climate event rather than a date — which is the form that survives being carried to a colder garden, a frost pocket, or next year.

Conditions it needs

Light: Full sun, Partial shade
Frost: Frost tender
Grows best at: 16–28 °C
Soil: Peat-free compost
Soil pH: 6–7
Drainage: Free-draining
Water needs: low
Drought: good tolerance
Waterlogging: poor tolerance
Heat: good tolerance
Wind and exposure: poor tolerance

Where these figures come from

LightSourced guidancemoderate confidence

Royal Horticultural Society: Hoya — position

Checked 2026-08-13

FrostSourced guidancehigh confidence

Royal Horticultural Society: Hoya — hardiness

Checked 2026-08-13

Grows best atSourced guidancemoderate confidence

Royal Horticultural Society: Hoya — temperature

Checked 2026-08-13

SoilSourced guidancemoderate confidence

Royal Horticultural Society: Hoya — soil

Checked 2026-08-13

Soil pHSourced guidancemoderate confidence

Plant Finder — Missouri Botanical Garden: Hoya carnosa — culture

Checked 2026-08-13

DrainageSourced guidancemoderate confidence

Royal Horticultural Society: Hoya — soil

Checked 2026-08-13

Water needsHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

DroughtHorticultural consensusmoderate confidence

The thick leaves are a genuine water store.

No external citation — see the evidence type above.

Checked 2026-08-13

WaterloggingHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

HeatHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

Wind and exposureHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

On your soil

Computed by comparing this plant's recorded requirements against each soil's recorded characteristics. A recorded horticultural fact overrides the comparison where GrowingHQ holds one.

Soil	Verdict	Why
Heavy clay	Works, with one condition	Hoya will crop on heavy clay, but one thing has to be dealt with first. It needs ground that drains, and this soil holds water. For a crop lifted before winter the risk is not rot but the season: waterlogged ground is cold and unworkable in spring, so sowing is late and germination patchy.Improve the drainage before planting — a raised bed, or bulky organic matter worked in over several seasons. Do not add sand to clay in small quantities; it makes the problem worse.
Sandy	Prefers this soil	Sandy suits Hoya as it stands: The pH suits it: it wants 6 to 7, and this soil is in that range. The free drainage is exactly what it wants. It stands dry conditions better than most, which this soil will test.
Chalky and alkaline	Works, with one condition	Hoya will crop on chalky and alkaline, but one thing has to be dealt with first. The soil is substantially too alkaline for it: it wants pH 6 to 7, and this soil sits around 7.8 to 8.5.The pH is the obstacle. Small shifts are achievable and slow; large ones are not. On chalky and alkaline the dependable answer is a container of the right compost rather than an attempt to change the ground.
Loam	Prefers this soil	Loam suits Hoya as it stands: The pH suits it: it wants 6 to 7, and this soil is in that range. The free drainage is exactly what it wants. The soil holds moisture, which saves a great deal of watering.
Silty	Prefers this soil	Silty suits Hoya as it stands: The pH suits it: it wants 6 to 7, and this soil is in that range. The free drainage is exactly what it wants. The soil holds moisture, which saves a great deal of watering.
Peaty and acid	Works, with one condition	Hoya will crop on peaty and acid, but one thing has to be dealt with first. It needs ground that drains, and this soil holds water. For a crop lifted before winter the risk is not rot but the season: waterlogged ground is cold and unworkable in spring, so sowing is late and germination patchy.Improve the drainage before planting — a raised bed, or bulky organic matter worked in over several seasons. Do not add sand to clay in small quantities; it makes the problem worse.
Shallow over rock	Prefers this soil	Shallow over rock suits Hoya as it stands: The free drainage is exactly what it wants. It stands dry conditions better than most, which this soil will test.
Made ground and urban soil	Works, with one condition	Hoya will crop on made ground and urban soil, but one thing has to be dealt with first. It needs ground that drains, and this soil holds water. For a crop lifted before winter the risk is not rot but the season: waterlogged ground is cold and unworkable in spring, so sowing is late and germination patchy.Improve the drainage before planting — a raised bed, or bulky organic matter worked in over several seasons. Do not add sand to clay in small quantities; it makes the problem worse.

Not sure which you have? Four hand tests will settle it.

Space and spacing

Mature height: 100–300 cm
Mature spread: 40–80 cm
Rooting depth: 15 cm

Where these figures come from

Mature heightHorticultural consensusmoderate confidence: No external citation — see the evidence type above.
Checked 2026-08-13
Mature spreadHorticultural consensusmoderate confidence: No external citation — see the evidence type above.
Checked 2026-08-13
Rooting depthHorticultural consensusmoderate confidence: No external citation — see the evidence type above.
Checked 2026-08-13

In a container

Minimum volume: 2 litres or more
Minimum depth: 12 cm

Where the container figures come from

Minimum volumeHorticultural consensusmoderate confidence: No external citation — see the evidence type above.
Checked 2026-08-13
Minimum depthHorticultural consensusmoderate confidence: No external citation — see the evidence type above.
Checked 2026-08-13

Keep it pot-bound. A hoya moved into a large pot puts its energy into roots and stops flowering for years.

Habit and ultimate size

What the plant becomes, rather than what it is when you buy it. The gap between the two is where most planting mistakes live.

Foliage: Evergreen
In a container: Good in a container long-term

Where these figures come from

FoliageSourced guidancehigh confidence: Royal Horticultural Society: Hoya carnosa — foliage
Checked 2026-08-13
In a containerHorticultural consensusmoderate confidence: No external citation — see the evidence type above.
Checked 2026-08-13

How it climbs: Twining — needs wires or thin supports to wrap around
Vigour: Restrained — suits a small structure

Where these figures come from

How it climbsSourced guidancehigh confidence: Royal Horticultural Society: Hoya carnosa — support
Checked 2026-08-13
VigourSourced guidancemoderate confidence: Royal Horticultural Society: Hoya carnosa — vigour
Checked 2026-08-13

Support it needs. An epiphytic twiner rather than a trailer, and it flowers far better trained up a hoop or a small trellis in the pot than left to hang. The long bare questing stems are how it climbs and should not be cut off.

Effect on what it grows over. Flowers come from short permanent spurs that bloom again year after year. Removing the spent flower head takes the spur with it and that stem will not flower again — the single most consequential thing to know about growing one.

source

Horticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

Where and how you can grow it

Each way of growing is assessed separately, and “not assessed” is a real answer rather than a gap we have filled in with a guess.

Method	Suitability	What it needs
Indoor pot	Well suited source Sourced guidancemoderate confidence Royal Horticultural Society: Growing method suitability Checked 2026-08-13
Windowsill	Well suited source Sourced guidancemoderate confidence Royal Horticultural Society: Growing method suitability Checked 2026-08-13
Container	Well suited source Sourced guidancemoderate confidence Royal Horticultural Society: Growing method suitability Checked 2026-08-13	Indoors, or outdoors in summer only
Greenhouse	Well suited source Sourced guidancemoderate confidence Royal Horticultural Society: Growing method suitability Checked 2026-08-13
Open ground	Not suitable source Sourced guidancemoderate confidence Royal Horticultural Society: Growing method suitability Checked 2026-08-13	Tender: will not survive a British winter outdoors.

Growing it

PruningDo not cut off the short leafless stalk left after flowering. Hoya flowers from perennial spurs and produces again from the same point each year; removing them is the commonest reason a healthy plant never flowers twice.
ProtectionLeave it where it is once buds appear. Hoya drops developing buds after a move or a sharp change in light, and the cluster is lost for that season.
PropagationStem cuttings root readily in spring and summer. Take a piece with two or three leaves and cut just below a node; roots come from the node and nowhere else. Never remove the flowering spurs from the parent — a hoya blooms from the same short stubs year after year, and cutting them off is why plants stop flowering.
WateringLet the compost dry most of the way through before watering, then soak it thoroughly — as an epiphyte it is adapted to a cycle of wetting and drying and dislikes being permanently damp. Cut back considerably from October; a hoya in a cool room over winter wants very little, and its thick leaves carry it through easily. The one rule that overrides everything: do not cut off the bare flower stalks after the blooms drop. It flowers again from the same short spurs year after year, and removing them is the commonest reason a mature hoya never repeats.
FeedingA half-strength balanced feed monthly through spring and summer, switching to a high-potash feed as buds appear, and nothing over winter. Hoyas flower best when slightly pot-bound and mildly stressed, so a plant repotted generously and fed hard characteristically produces long leafy vines and no flowers at all — the correct response to that is patience and brighter light rather than more fertiliser.

Where this guidance comes from

PruningSourced guidancehigh confidence: Royal Horticultural Society: Hoya — pruning
Checked 2026-08-13
ProtectionSourced guidancemoderate confidence: Royal Horticultural Society: Hoya — flowering
Checked 2026-08-13
PropagationSourced guidancemoderate confidence: Royal Horticultural Society: Hoya — cultivation
Checked 2026-08-13
WateringSourced guidancehigh confidence: Royal Horticultural Society: Hoya carnosa — cultivation
Checked 2026-08-13
FeedingSourced guidancemoderate confidence: Royal Horticultural Society: Hoya carnosa — cultivation
Checked 2026-08-13

The bud you cut to becomes the new shoot, and it grows in the direction it points — which is why an outward-facing bud opens the plant up and an inward-facing one crosses the middle.

The rule is the same in all four: the new piece needs both a growing point and roots of its own. A cutting is the exception that has to make its roots afterwards, which is why the node matters so much.

What goes wrong

Problem	How often	Notes
Pruned at the wrong time	common source Horticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13	Cutting off the spent flower spurs removes the wood next year's umbels come from.

Start from what you can see

White fluff in the leaf joints

Safety and edibility

Cats and dogs

Listed as non-toxic to cats and dogs

Hoya appears on published non-toxic lists for cats and dogs. That is a statement about the plant's chemistry, not a guarantee: any plant eaten in quantity can upset an animal, so it is still worth discouraging heavy chewing.

source

Sourced guidancehigh confidence

ASPCA Animal Poison Control Center — toxic and non-toxic plant list — American Society for the Prevention of Cruelty to Animals: Hoya carnosa — non-toxic plants list

Checked 2026-08-13

Sources for this page

GrowingHQ editorial synthesis · Plant Finder · Royal Horticultural Society

Each figure on this page carries its own citation, under the “where these figures come from” note in its section. Record last reviewed 2026-08-14.