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A gerbera grows from a short thick crown at soil level, and every leaf and flower stem comes out of that one point. If the crown is buried, or if water collects in the cup of leaf bases, it rots. The rot is quiet for a week and then sudden: the outer leaves go limp, the center turns brown and soft, and a plant that looked healthy on Monday pulls out of the pot with no roots on Friday. More gerberas are lost this way than to any pest.
Set the plant so the crown stands about half an inch (1 cm) proud of the surrounding soil, sitting on a slight mound rather than in a dish. Fresh potting mix settles by an inch or more in the first month of watering, so a crown planted flush ends up buried by early summer without anyone touching it. Check the level again a month after planting and scrape mix away from the center if it has crept up over the leaf bases.
Do not mulch up to the crown, and do not let fallen leaves or spent petals sit in the middle of the plant. Anything that holds moisture against that short stem is doing the same job as burying it.
Look down into the center of the plant once a week. You should be able to see bare crown and the clean bases of the leaf stalks. If you see damp mix, decayed petals or a slimy brown ring, clear it out that day.
Water at the edge of the pot, never over the plant
Pour water onto the soil at the rim, working around the pot, so that it soaks in from the outside and reaches the roots without ever running through the center of the crown. A watering can held over the foliage does the opposite: it fills the leaf cup, wets the crown, and leaves droplets sitting on hairy leaves that dry slowly. Overhead watering is the single habit most worth breaking with this plant.
Let the top inch (2.5 cm) of mix dry before watering again. Push a finger in rather than judging by the surface, which dries fast on a hairy-leaved plant that shades its own soil. In warm bright weather an established plant in a six inch (15 cm) pot wants water every three to four days; in a cool dull spell it can go a week and a half. Water when the plant asks, not on a fixed day.
Water thoroughly when you do water, until it runs out of the drainage holes, then empty the saucer within ten minutes. Gerberas will not tolerate standing water at the base any more than they tolerate it at the crown. A pot left in a full saucer through cool weather is the second most common way to lose one.
A gerbera that wilts at midday in strong sun and recovers by evening is not short of water. A gerbera that wilts and stays wilted after a thorough soak has lost roots, and the cause is almost always rot rather than drought.
| Situation | How often | What to check |
|---|---|---|
| Pot outdoors, warm bright weather | Every three to four days | Top inch (2.5 cm) dry to a finger |
| Pot indoors on a bright sill | Every seven to ten days | Pot noticeably lighter when lifted |
| Cool dull spell or winter | Every ten to fourteen days, less if cold | Never leave mix wet at the crown |
| In the ground, established | A deep soak once a week in dry weather | Soak the soil around the plant, not the center |
| Newly planted | Every three days for two weeks | Original root ball damp, crown still proud |
Give it far more light than you think
Gerberas are sold as decorative pot plants and then put on a coffee table, where they flower for three weeks and never again. They are full sun plants. Outdoors they want six hours or more of direct sun, with light shade only through the hottest part of the afternoon in a hot climate. Indoors they need the brightest window in the house, close to the glass, and even then they flower less freely than the same plant outside.
The symptom of too little light is unmistakable once you know it: long soft leaf stalks that flop outward instead of standing up, a plant that spreads wider and wider with an empty center, and buds that form and then abort at half an inch. Feeding a plant in that state makes it floppier. Moving it into sun turns it around in three to four weeks.
Move a plant into full sun gradually if it has been in low light. Two weeks of shade-grown leaves scorch in a day of unfiltered sun, showing as bleached patches that dry to brown paper. Give it a few hours of morning sun for a week first, then full exposure.
Feed lightly and often once it is growing
A gerbera in a pot is in a small volume of mix and exhausts it within about six to eight weeks. Once the plant is in active growth, feed a balanced liquid fertilizer at half strength every two weeks, or at quarter strength with every watering. Stop feeding in cold weather when the plant is barely growing, because unused fertilizer salts build up in the mix and burn the fine roots.
If the plant is making large lush leaves and few flowers, the feed is too high in nitrogen. Switch to one higher in potassium, on the pattern of a tomato feed, and the balance shifts back towards buds within a month. Pale leaves with green veins on the newest growth is a different problem, usually iron lock-up in mix that has drifted alkaline under hard tap water, and a chelated iron feed corrects it in ten days.
Flush the pot with plain water once a month in the growing season, pouring twice the pot volume through at the rim to wash out accumulated salts.
Grooming: remove old leaves and pull spent stems out
Take off the outer leaves as they yellow, rather than letting them collapse onto the crown and rot there. Grip the leaf stalk low down and pull it sideways and outward with a short sharp tug; it comes away cleanly at the base. Cutting the stalk halfway leaves a stub that decays inward towards the crown, which is exactly where you do not want decay.
Do the same with a flower stem once the bloom is finished. Follow the stem down into the crown, take hold of it low, and pull it sideways with one decisive tug rather than a slow drag. A healthy stem detaches with a small snap and leaves nothing behind. Snipping the stem with scissors leaves a hollow stub that fills with water at the next watering and rots the crown from the inside. This one detail separates gerberas that last several years from gerberas that last one summer.
Go over the plant once a week in the growing season. It takes two minutes and it is most of the maintenance a gerbera ever needs.
- Work on a dry plant Leaf stalks and flower stems detach cleanly when the plant is turgid and the crown is dry. Doing this straight after watering tears tissue and leaves wet wounds.
- Grip low, close to the crown Take the stem between finger and thumb as near the base as you can reach. Holding it halfway up snaps the stem and leaves the base behind.
- Pull sideways, not upward One firm sideways tug away from the center of the plant. Pulling straight up drags at the crown and can lift the whole plant out of the mix.
- Check what came away The base of the stem should be a clean white or pale point. A soft brown base means rot is already in the crown and the mix needs opening up and drying out.
Temperature and air movement
Gerberas grow best between 60F and 75F (16C and 24C). Above about 85F (29C) they keep their leaves but slow bud production, and the flowers that open are smaller and shorter lived. Below about 45F (7C) growth stops. They are not reliably hardy through a freeze, and a crown that freezes while wet does not come back.
Air movement around the leaves matters more here than on most plants, because the two main problems, powdery mildew and crown rot, both thrive in still humid air around a dense rosette. Space plants so their leaves do not overlap, keep pots off a crowded shelf, and thin the oldest leaves on a plant that has become a solid dome of foliage.
Keep a note of the position each pot stood in and how it flowered. Sun exposure decides more about a gerbera's performance than anything you buy, and the same corner of a patio behaves the same way every year.