Yellow leaves at the bottom of the plant
The commonest complaint in the journal. Usually watering, sometimes age, occasionally light or feeding, and how to tell which one you have.
What it usually is
1 Too much water, or a pot that cannot drain
| How to tell | Push a finger into the compost to the second knuckle. If it is damp and the lower leaves are yellowing softly rather than drying, this is your answer. Lift the pot: a pot that stays heavy for days after watering is holding water the roots cannot use. |
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| The fix | Stop watering and let the compost dry until the top third is dry to the touch. Empty the saucer every time. If the pot has no drainage hole, move the plant into one that has, and mix grit or perlite into the compost if it stays wet for more than a week. |
2 The plant is retiring an old leaf
| How to tell | One or two leaves at the very bottom, yellowing evenly while everything above is firm and green, and new growth is coming at the top. This is a plant balancing its books, not a plant in trouble. |
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| The fix | Nothing. Pull the leaf away once it comes free with a gentle tug, or cut it off at the stem. A plant that sheds one lower leaf a month and grows two new ones at the top is doing well. |
3 Not enough light
| How to tell | The yellowing works up from the bottom over weeks, the newer leaves are smaller than the old ones, and the gaps between leaves on the stem are longer than they used to be. |
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| The fix | Move it closer to a window or into a brighter room. A plant cannot pay for leaves it cannot light, so it drops the ones furthest from the sun first. |
4 Hungry, after a long time in the same compost
| How to tell | A plant that has been in the same pot for more than a year, yellowing generally rather than only at the bottom, with the older leaves going pale between the veins first. |
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| The fix | Feed at the strength on the bottle through the growing season, or repot into fresh compost. Never feed a plant that is sitting in wet soil, which adds salts to roots that are already struggling. |
Through the year. Yellow lower leaves in autumn and winter are usually watering, because the plant is using far less than it did in July and the same jug is still coming round every week. Yellowing in spring on a plant that has grown well is more often hunger or a pot it has outgrown.
Yellow leaves at the bottom of a plant are the single commonest thing people write to us about, and the answer is nearly always in the pot rather than in the leaf. Roots need air as much as they need water. Compost that never dries holds no air, the fine roots that do the actual drinking die back, and the plant, unable to move water up, does exactly what a thirsty plant does: it sheds from the bottom. That is why an overwatered plant so often looks like a thirsty one, and why the instinct to water it again is the thing that finishes it off.
So begin with the soil, not the leaf. A finger to the second knuckle tells you more than a week of watching does. Damp and yellow means stop; dry and yellow means look further.
The second thing to look at is where the yellowing is. Old leaves at the bottom, one or two at a time, on a plant that is putting out new growth at the top, is ordinary retirement. Every plant does it. Yellowing that climbs steadily, or that appears on several leaves at once, or that reaches the newer growth, is the plant telling you something is wrong with its conditions.
Light is the quiet cause. A plant moved from a bright nursery to a corner two metres from a window cannot support the leaf area it arrived with, and it sheds the lowest leaves first because those are the ones in deepest shade. This is slow, it takes weeks, and it stops when the plant is moved somewhere brighter.
Hunger is the least common of the four and the easiest to overdo. A plant in fresh compost has enough for a couple of months. After a year in the same pot it does not, and pale yellowing between green veins on older leaves is the sign. Feed at the strength on the bottle, in the growing season only, and never into dry compost or wet.
Two things not to do. Do not cut off every yellow leaf the moment you see it: a leaf on its way out is being emptied of everything useful, and taking it early costs the plant. And do not repot a plant that is yellowing from wet compost into a larger pot, which gives it more wet compost to sit in. Let it dry first, then decide.
Entries that name it
What the journal says about this symptom on each plant.
| Alocasia | Overwatering, or the plant shedding a leaf as a new one opens. Check the compost first. This plant keeps only a few leaves at a time and loses an old one for each new one. |
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| Areca palm | An old frond dying back naturally, or a shortage of magnesium. One lower frond at a time is normal. Widespread yellowing between the veins is a feed problem and needs a feed with trace elements. |
| Arrowhead vine | Overwatering. Let the top 3 cm dry between waterings and check the pot drains. |
| Asparagus fern | Too little light, or a pot so full of roots there is no compost left. Move it brighter and tip it out to look. If the pot is solid root, divide the clump in spring or move it up a size. |
| Bird of paradise | Overwatering in winter, or an old leaf being shed. Cut winter watering back sharply. One old outer leaf yellowing at a time is normal on a growing plant. |
| Blushing philodendron | Overwatering in a mix that holds too much water. Repot into a coarse bark based mix and let the top 4 cm dry between waterings. |
| Boston fern | Waterlogged compost, or too much feed. Let the surface dry slightly before watering, make sure the pot drains, and halve the feed. |
| Caladium | Autumn arriving, which is normal, or cold at any other time. If the days are shortening, let it die down and store the tuber dry. If it is midsummer, check the room is above eighteen degrees. |
| Calathea | Waterlogged compost, or cold. Check that the pot drains and that the room stays above 16 degrees. Let the surface dry slightly before watering again. |
| Cast iron plant | Wet compost, which is the only reliable way to kill it. Let it dry well down between waterings, and in winter that may be a month. |
| Chinese evergreen | Overwatering, or an old leaf being shed as the stem lengthens. Check the compost. Damp means water less and improve the drainage; one leaf at a time on a growing plant is normal. |
| Chinese money plant | Overwatering, or the plant shedding its oldest leaves as the stem lengthens. Check the compost first. A bare lower stem with a tuft on top is normal for an older plant and is part of its shape. |
| Chives | A clump that has become congested, or a pot that has run out of food. Divide it in spring, replant a third of it in fresh compost, and give the rest away. |
| Common jasmine | Cold wet soil in winter, or a pot that has run out of root room. Improve the drainage at the base of the wall and mulch. In a container, move it up a size and use fresh compost. |
| Coriander | Waterlogged compost, or a plant that has finished and is going over. Check the drainage. A plant that has flowered is at the end of its life and should be replaced rather than nursed. |
| Corn plant | Old leaves shed as the cane lengthens, or overwatering. A steady loss from the bottom is how it builds a trunk. Several at once with damp compost is too much water. |
| Daffodil | Normal die back after flowering, or narcissus bulb fly grubs in the bulb. Yellowing in late spring is the plant storing its year and should be left. Bulbs that come up thin and grassy year after year are infested and should be dug out. |
| Dragon tail | Compost kept too wet. Let the top third dry out between waterings. It is more drought tolerant than it looks. |
| Dragon tree | Old leaves being shed as the stem lengthens, or overwatering. A steady loss of the lowest leaves is normal and is how the plant makes its trunk. Several at once with damp compost is too much water. |
| Dumb cane | Overwatering, or the plant shedding old leaves as the stem lengthens. Feel the compost. Damp means water less and check the drainage; a slow steady loss from the bottom is how it makes a trunk. |
| Elephant's ear | Autumn, which is normal, or a shortage of feed in midsummer. If the days are shortening, let it die down. Otherwise feed it fortnightly, because it is a very hungry plant. |
| English ivy | Waterlogged compost, or a plant that has dried out completely and is shedding. Feel the compost. Damp means water less and check drainage; bone dry means water more evenly and cut back the worst stems. |
| Flamingo flower | Overwatering in a mix that holds too much water. Repot into a coarse bark based mix, water only when the top 3 cm is dry, and make sure the pot drains freely. |
| Garlic | Ripening, if it is early summer, or waterlogged ground if it is winter. Yellowing tops in summer mean it is nearly ready. Yellowing in a wet winter means the drainage needs help. |
| Heartleaf philodendron | Overwatering, or an old leaf being shed by a long stem. Feel the compost before deciding. Damp compost means water less; a single old leaf at the base of a long stem is normal. |
| Kale | Old leaves shed as the stem lengthens, or hunger in a pot. Strip the yellow leaves off cleanly to keep air moving, and feed a container grown plant through summer. |
| Kentia palm | An old frond dying back, or waterlogged compost. One at a time is normal. Several at once with wet compost means the roots are drowning. |
| Lady palm | An old frond dying back, or overwatering. One at a time is normal. Several at once with wet compost means the roots are drowning. |
| Lavender | Waterlogged roots, or a rich soil holding too much moisture. Improve the drainage with grit, stop watering an established plant, and move a potted one out of its saucer. |
| Lucky bamboo | Water that has been left too long, too much feed, or direct sun. Change the water weekly, feed at a tenth strength at most, and move it out of any sun beam. |
| Ming aralia | Wet compost in a cool room. Let the top third dry between waterings and keep it above fifteen degrees. |
| Money tree | Compost kept wet, which is what almost every unhappy money tree is suffering from. Let the top half dry between waterings and check the pot drains. A tree in a decorative sleeve with no hole is the usual culprit. |
| Moth orchid | An old leaf being shed, or water sitting in the crown. One bottom leaf yellowing slowly is normal. Water in the sink and tip the plant to empty the crown, because water left there rots the growing point. |
| New Zealand broadleaf | Waterlogged soil, which this plant does not tolerate despite otherwise being one of the easiest hedging shrubs available. Improve drainage before replanting rather than trying to nurse a hedge planted in ground that sits wet. This is one of the few genuine ways to lose it. |
| Onion | The natural end of the season as the bulbs ripen, or waterlogged ground. If it is midsummer and the tops are falling over, that is ripening. If it is early and the soil is wet, improve the drainage. |
| Parlour palm | An old frond dying back, or waterlogged compost. One lower frond at a time is normal. Several at once, with damp compost, means the roots are drowning. |
| Peace lily | Overwatering or old age of the leaf. Let the top of the mix dry slightly between waterings; remove old leaves cleanly. |
| Pothos | Overwatering. Let the mix dry further between waterings and check drainage. |
| Prayer plant | Wet compost, or a room that is too cold. Let the surface dry slightly before watering, check the pot drains, and keep the room above 15 degrees. |
| Ribbon fern | Too much light, or hard water building up in the compost. Move it out of the sun and flush the pot through with rainwater every couple of months. |
| Rubber plant | Overwatering, or the plant shedding old leaves as it grows taller. Check the compost first. If it is damp, water less and let it dry further. One old leaf lost occasionally from the bottom of a growing plant is normal. |
| Satin pothos | Overwatering. Let the top half of the compost dry between waterings and check the pot drains. |
| Song of India | Compost kept wet, or simply the oldest leaves going as the cane lengthens. Let it dry down between waterings. A leaf or two a month from the bottom of an old cane is normal. |
| Swiss chard | Old leaves shed as new ones come, or hunger in a container. Pick the outer leaves regularly and feed a container plant monthly. |
| Swiss cheese plant | Overwatering or a mix that stays wet. Let the mix dry further between waterings and check the pot drains. Remove fully yellow leaves. |
| Swiss cheese vine | Watered again before the compost dried. Let the top third dry out. In a plastic pot in winter that can be three weeks. |
| Tomato | The oldest leaves being shed, a shortage of feed, or waterlogged roots. Feed weekly once fruit has set, check the drainage, and remove the lowest leaves as they go. |
| Tree philodendron | Compost kept wet, which is the usual story with a large aroid. Let the top third dry out before watering again and check the pot actually drains. One or two old leaves yellowing a year is normal. |
| Wax plant | Overwatering in a mix that holds too much water. Repot into a bark based mix, let the compost dry most of the way through between waterings, and check the pot drains. |
| Weeping fig | Overwatering, or the plant dropping old leaves after a light change. Feel the compost. Damp means water less and check the drainage; dry with a recent move means simply wait. |
| Yucca | Old leaves being shed as the cane grows, or overwatering. A steady loss of the lowest leaves is normal and is how the trunk forms. Several at once with damp compost is too much water. |
| Zebra alocasia | Wet compost in a cool room, or the plant going dormant in winter. Ease off the water from autumn. If it loses every leaf and the corm is firm, keep it barely damp and it will come back in spring. |
| ZZ plant | Overwatering, and the beginning of rhizome rot. Stop watering, check the rhizomes are firm rather than soft and brown, and cut away any that have gone. Let the compost dry completely before the next drink. |
Questions from the margin
- Why are my plant's bottom leaves turning yellow?
- Nearly always watering. Put a finger into the compost to the second knuckle: if it is damp and the lower leaves are yellowing softly, the plant is being watered more often than it can use, and the fine roots are suffocating. If the compost is dry and only one or two leaves are going, it is ordinary old age.
- Should I cut off yellow leaves?
- Not immediately. A leaf on its way out is being emptied of everything the plant can reuse, so cutting it early costs the plant a little. Wait until it comes away with a gentle tug, or until it is more yellow than green, then remove it at the stem.
- Can a yellow leaf turn green again?
- No. The tissue has already been emptied. Judge whether you have fixed the problem by watching the next new leaf, not the ones already yellow.
Checked against RHS, Houseplants: yellowing leaves; Missouri Botanical Garden, Plant Finder cultural notes.