How to Care for a Lemon Tree, Indoors or Out
At a glanceA lemon tree rewards steady attention with glossy leaves, scented blossom and fruit for the kitchen. Most of its needs come down to light, water and warmth.
There is something cheering about a lemon tree. The leaves stay glossy all year, the blossom fills a room with scent, and every so often you get a fruit you grew yourself. Lemons have a reputation for being fussy, but most problems come from a handful of predictable mistakes. Get the basics right and a healthy tree will carry on for many years, whether it lives on a sunny windowsill or in a garden bed.
Choose the right variety
Some lemon types stay compact and cope well in pots, while others grow into substantial trees that need open ground. Dwarf and naturally smaller varieties are the usual choice for containers and indoor growing. If you are still deciding, our guide to the varieties of lemon trees and their traits compares the most common ones.
Light: as much as you can give
Lemons are sun lovers. Outdoors, choose the sunniest, most sheltered spot you have, ideally protected from cold winds. Indoors, place the tree by the brightest window, usually one facing south in the northern hemisphere. If the leaves look pale or the tree stretches toward the glass, it probably needs more light. A plant grow light can help through dark winters.
Watering without drowning
Overwatering is one of the most common ways to harm a lemon tree. The roots need moisture but also air.
- Water thoroughly, then let the top few centimetres of soil dry out before watering again.
- Check by pushing a finger into the soil rather than following a fixed calendar.
- Make sure pots have drainage holes, and do not leave the tree standing in a saucer of water.
- In summer and in warm rooms you will water more often; in winter, much less.
Soil and pots
A free-draining mix is essential. Specialist citrus compost is the easiest option for containers; otherwise, a good potting compost with added grit or bark improves drainage. Choose a pot only slightly larger than the root ball, and move up a size every couple of years in spring. In the ground, lemon trees prefer soil that drains well and does not stay soggy after rain.
Feeding
Lemons are hungry plants, particularly in pots where nutrients wash out with every watering. Use a fertiliser formulated for citrus and follow the product label. Many growers use a summer feed during the growing season and a winter feed in the cooler months. Yellowing between the leaf veins can be a sign the tree is short of nutrients.
Warmth and winter care
| Situation | What to do |
|---|---|
| Potted tree in a cold climate | Bring it indoors or into a frost-free greenhouse or conservatory before the first frost |
| Indoor tree near a radiator | Move it away from direct heat, which dries leaves and soil quickly |
| Dry indoor air | Stand the pot on a tray of damp pebbles, keeping the base above the water |
| Tree in the ground in a mild area | Protect with horticultural fleece during unusually cold nights |
| Moving outdoors in spring | Acclimatise gradually over a week or two to avoid leaf scorch |
Pruning and shaping
Lemon trees need little pruning. In late winter or early spring, remove dead or crossing branches, trim any shoots growing from below the graft union on grafted trees, and shape the tree to let light into the centre. Wear gloves, as many lemons have sharp thorns.
Flowers and fruit
Indoor trees may need a helping hand with pollination. Gently brushing the inside of each open flower with a small, soft paintbrush can help fruit set. Do not worry if a young tree drops some of its small fruits; trees often shed what they cannot support. Lemons can take many months to ripen, and they are ready when fully coloured and slightly soft to a gentle squeeze.
Common problems and quick fixes
- Leaf drop: often caused by sudden changes in temperature, light or watering. Keep conditions steady.
- Yellow leaves: check for overwatering first, then consider feeding.
- Sticky leaves or tiny insects: scale insects, aphids and mealybugs are common indoors. Wipe leaves with a damp cloth and check undersides regularly.
- Fine webbing: a sign of spider mites, which like warm, dry air. Raise humidity and rinse the foliage.
Enjoying the harvest
Homegrown lemons are lovely in dressings, baking, marinades or simply a slice in hot water. A healthy tree does not ask for much: plenty of light, careful watering, regular feeding and protection from the cold. Give it those, and it will stay a bright, fragrant companion in your home or garden for years.
