A plant short of light does not die quickly. It stretches, pales, stops flowering and slowly thins out, and because each change is gradual the cause is easy to miss. This guide lists the signs in the order they usually appear, explains which other problems mimic them, and sets out where to move the plant in an Australian garden or home, and when.
Signs your plant needs more sun
Houseplants show these first, because indoor light is a fraction of what the same plant gets outside, but every sign below applies in the garden too.
Stretching and leaning
The earliest sign. New stems grow long and thin with wide gaps between the leaves, and the whole plant leans toward the window or the open side of the bed. The plant is spending its energy reaching for light rather than building leaves.
Pale or yellowing leaves
Leaves lose their depth of green, newest growth first, and may yellow evenly across the plant. The same look can come from a nitrogen shortage, so check the position before you reach for fertiliser; our guide to recognising plant deficiencies covers how to tell a nitrogen shortage from a light shortage.
Loss of colour and variegation
Coloured and variegated plants need light to make their pigments. Burgundy cordylines fade to green, silver foliage goes dull and cream-edged leaves come through plain green. The plant is not sick; it is making the most of the light it has.
Fewer or no flowers
Flowering takes more energy than leaf growth, so it is the first thing a plant gives up. A healthy, well-fed plant that will not flower is almost always short of light.
Stalled growth and bare stems
Growth slows or stops, lower leaves drop and the base of the plant goes bare while a few leaves hang on at the tips. Larger, thinner, darker leaves than normal are part of the same response, as the plant tries to catch more light with each leaf.
Soil that stays wet
A plant in low light uses little water, so the mix stays wet for a week or more after watering. Keep watering on the old schedule and the roots rot, which is why low light and overwatering so often arrive together.
What is not a light problem
Wilting can mean too little light, but far more often it means too much water or too little, so feel the soil first. Brown tips are the most misread symptom in gardening. Our guide to why plant leaves turn brown separates the watering causes from the light and salt causes. And a plant that has been moved into brighter conditions and developed bleached patches has the opposite problem; our guide to understanding leaf burn covers the bleached patches and crisp margins that mean you have moved a plant too far the other way.
Reading light in an Australian garden
Light advice written for the northern hemisphere is actively misleading here, because the sun tracks through the northern sky rather than the southern. The aspects invert completely.
| Aspect | Light in Australia | Suits |
|---|---|---|
| North-facing | The sunniest. Full sun most of the day | Sun-loving plants, fruit, vegetables |
| East-facing | Morning sun, afternoon shade, the gentlest | Almost anything; ideal for gardenia, camellia, ferns |
| West-facing | Shaded until midday then intense afternoon heat | Only genuinely tough plants |
| South-facing | The shadiest. Bright but little direct sun | Ferns, clivia, xanadu, mondo |
If you have read that a south-facing wall is the sunny one, that advice came from the northern hemisphere and will cost you plants.
Australian sun is stronger than most references assume
Ultraviolet levels across Australia are among the highest in the world, and "full sun" here is not the same quantity of light as full sun in Britain or northern Europe. A plant labelled full sun by an overseas source may well scorch in an open western position in Perth, Adelaide or inland Queensland. The practical translation: treat overseas "full sun" as Australian "morning sun with afternoon shade" for anything with soft or broad leaves, and reserve genuinely open western positions for natives, succulents and Mediterranean plants.
Signs it is getting too much
- Bleached, silvery or papery patches in the middle of leaves: sunburn, not disease.
- Brown crispy edges combined with wilting in the afternoon.
- Yellowing of the whole plant despite adequate watering.
- Variegated foliage scorching first, because pale tissue has no protective pigment.
Where to move it
Indoors, the first move is simply closer to the glass: light falls away sharply with every metre from a window, and a plant two metres back gets a fraction of what one on the sill gets. An east window is the safe choice for almost anything; a north window suits sun-lovers set back a little or behind a sheer curtain. Outdoors, move a stretched plant from shade into morning sun before trying full sun.
Sometimes the honest answer is that the plant is wrong for the position. If the spot bakes all afternoon, choose from our 15 low-maintenance plants that thrive in full sun or the plants for full sun range. If it never sees direct light, our shade gardening guide and the low light indoor plants range will serve you better than moving a sun-lover around the house.
When and how to move it
Move garden plants in autumn across most of Australia, or in spring for tropical species. Never move anything in the middle of summer; a plant already stressed by heat and light will not cope with root disturbance on top of it. Water thoroughly the day before, dig a wide root ball rather than a deep one, replant at the same depth immediately, and water in well. Harden the plant off gradually if it is moving into brighter conditions: a week in part shade before full sun prevents the scorch that comes from moving straight from a shaded position into an open one. Indoors, shift a plant in stages over a fortnight rather than straight from a dim corner to a hot sill.
Ready to plant?
Match the plant to the light you have rather than fighting it, and most of these symptoms never appear. Browse our sun-tolerant trees and plants for the positions that get the full day.
