How to keep a supermarket plant alive once you get it home

You went in for milk and came out with a peace lily. It happens to all of us. The plant looked perfect in the trolley, glossy and full and sitting in a little plastic sleeve with a picture on it, and now it is on your kitchen counter and you are not entirely sure what to do next. Two weeks later the leaves are yellowing, the soil smells a bit sour, and you have quietly decided you are not a plant person. You are. The plant just arrived with a few problems built in, and most of them are easy to fix in the first hour it spends in your home.

We repot a lot of these at the nursery for customers, and the same handful of things go wrong every time. The plant is sitting in a pot with no drainage, or a sealed sleeve that traps water. It has been grown fast in a greenhouse and is not used to a normal house. And it gets watered far too much by someone who is trying hard to keep it alive. Here is what we would do with it, in the order we would do it.

Where that plant has actually come from

A supermarket houseplant has had a strange life. It was grown in a commercial greenhouse under high humidity and bright, even light, fed to grow quickly, and packed off to a distribution centre while it still looked its best. Then it spent a few days in a truck and on a shelf under fluorescent light, often in a display with no natural light at all. By the time it reaches you it is tired, its soil is usually either sodden or bone dry, and it has never once experienced the dry Highveld air or the cold draught from a Cape window. None of this means it is a bad plant. It just means the first few weeks are about letting it adjust, not pushing it to perform.

Take off the sleeve and look at the roots

The first thing to do, before you even decide where it will live, is get it out of the packaging. Peel off the decorative sleeve or foil and lift the plant gently out of its plastic nursery pot. Have a look at the roots. If they are a dense white or cream mat wound round and round the outside of the soil, the plant is rootbound and has been in that pot too long. If they are brown, soft and smell of drains, it has been sitting in water and you have caught it just in time. If the soil is a solid dry brick that falls away in one piece, it has been dry for a while and will need a good soak before anything else. Illinois Extension's guide to repotting houseplants lists roots circling the outside of the pot and water running straight through as the two clearest signs that a plant needs a bigger home, and most supermarket plants show at least one of them.

Tease a few of the outer roots loose with your fingers, snip off anything black or mushy with clean scissors, and check the leaves and stems for pests while you are there. Mealybug and spider mite love a greenhouse and travel home with the plant more often than you would think. Our quick guide to potted plant pests shows you what to look for.

Give it a week before you do anything drastic

If the roots look healthy and the soil is fine, resist the urge to repot on day one. Put the plant, still in its nursery pot but out of the sleeve, on a saucer somewhere with bright, indirect light and no cold draughts, and leave it for a week or two. This is acclimatising, and it matters more than people think. The plant is moving from a humid, bright greenhouse into a room that is drier and dimmer, and it needs time to adjust its leaves to the new conditions. Some leaf drop in this period is normal, especially on ficus and the fussier ferns. A few yellow leaves at the bottom is the plant reshuffling, not dying. Repotting on top of that shock, in the same week, is what tips a lot of borderline plants over the edge. If the roots are rotting or the pot has no drainage at all, skip the wait and repot straight away, because those problems will not improve on their own.

Repot into something with a hole in it

When it is time, choose a pot only a little bigger than the one it came in, two to four centimetres wider is plenty. A huge jump in size leaves the roots surrounded by soil they cannot use, and that soil stays wet and turns sour. Whatever you pick must have a drainage hole. The pretty ceramic cache pot with a sealed base is exactly how supermarket plants drown, because water collects in the bottom where you cannot see it. Every pot we cast has a hole, and for indoors we sell drip trays separately so the water can leave and your floor stays dry.

Use a proper indoor mix rather than garden soil or the old soil from another pot. Indoor Potting Soil is lighter and drains faster than outdoor mixes, which is what you want when the pot sits in a room with no wind or sun to dry it. Set the plant so the top of its rootball sits a finger's width below the rim, firm the mix gently around the sides, water once until it runs out the bottom, and then leave it alone. If you want the pot to look good without weighing a ton on a shelf, our Lightweight Décor range was made for exactly this job. For a bigger plant on a patio or in a bright entrance hall, the patio and small garden favourites are cast from Fibre Concrete Mix and can live indoors or out.

Water less than you think

This is where most supermarket plants die. People water on a schedule, every Sunday say, whether the plant needs it or not. A plant in a cool room in June needs a fraction of the water it needed in a greenhouse in January. The Illinois Extension notes on watering houseplants are blunt about it: more houseplants are killed by overwatering than by anything else, and the amount a plant needs depends on its size, the light it gets and the season, not the calendar.

So use your finger. Push it into the soil up to the second knuckle. If it feels damp, walk away. If it feels dry, water thoroughly until it drains, tip the excess out of the tray after twenty minutes, and do not come back until it is dry again. In a Gauteng winter that might be every two weeks for a peace lily and every month for a snake plant. In a humid Durban summer it might be twice a week. The plant will tell you if you let it, and drooping leaves that perk up an hour after watering are a far better signal than a reminder on your phone. Our houseplant care guide goes deeper on reading those signals for the most common plants.

Bright, but not baking

Almost everything sold as a houseplant wants bright light without direct sun on its leaves. In practice that means near a window but not pressed against the glass, especially a west facing window in summer where the afternoon sun through glass will scorch a fern or a calathea in an afternoon. The Illinois Extension page on houseplant lighting explains why light is the factor that limits most indoor plants: without enough of it they cannot use the water you give them, which is how low light and overwatering end up killing plants together. A room that feels bright to you is often quite dim to a plant, so err towards more light and watch the leaves. Pale, stretched new growth means too little. Bleached or crispy patches mean too much direct sun.

When to worry and when to wait

Yellow leaves at the base in the first fortnight are adjustment. Yellow leaves all over with wet soil are overwatering, so stop, let it dry, and check the roots. Brown crispy edges usually mean dry air or a missed watering, which is common in our winters when the heaters are on. Sticky leaves or fine webbing mean pests. A plant that looks dreadful for a month and then pushes out one clean new leaf is going to be fine, and that new leaf is the sign to look for. The RHS houseplant pages are a good reference when you want to check what a particular plant expects, and our own Plant Library lets you look up light and water needs for the plants we see most often in South African homes.

The plant from the trolley is not a lost cause. Get it out of the sleeve, check the roots, give it a week to settle, move it into a slightly bigger pot with a drainage hole and fresh indoor soil, and water only when it is dry. That is the whole method, and it turns a two week plant into one that is still with you years later. If it needs a permanent home, our patio and small garden favourites include pots that suit an entrance hall or a sunny kitchen just as well as a stoep.

Frequently asked questions

Why do supermarket plants die so quickly at home?

They are grown fast in humid, bright greenhouses, sold in sleeves or pots without drainage, and then usually overwatered in a room with much less light. Fixing the drainage and watering less solves most of it.

Should I repot a new plant straight away?

If the roots are healthy, wait a week or two so the plant can adjust to your home first. If the pot has no drainage hole or the roots are brown and soft, repot immediately.

What size pot should I move a new houseplant into?

Only two to four centimetres wider than the pot it came in. A much larger pot holds soil the roots cannot use, and that soil stays wet and causes rot.

How often should I water a houseplant in South Africa?

There is no fixed schedule. Push a finger into the soil to the second knuckle and water only when it feels dry. In winter that may be every two to four weeks; in a hot, humid summer it can be twice a week.

Can I use garden soil to repot an indoor plant?

No. Garden soil compacts and drains poorly in a pot. Use a light indoor potting soil and a container with a drainage hole and drip tray.