How to grow an orange tree in the UK
Updated: October 2026
The tree is already on the kitchen floor, still in the nursery pot, and the first cold night is in the forecast. You cannot plant it in the border and hope. Citrus in Britain is a pot you move: outside after the frosts, back under glass when the nights drop, and watered less in December than in July. This page is that year, for a live orange or calamondin you already have. It does not rank the listings. The [orange tree comparison](/hub/trees-and-palms/orange-tree) does that.
The tree is already on the kitchen floor, still in the nursery pot, and the first cold night is in the forecast. You cannot plant it in the border and hope.
The tree is already on the kitchen floor, still in the nursery pot, and the first cold night is in the forecast. You cannot plant it in the border and hope. Citrus in Britain is a pot you move: outside after the frosts, back under glass when the nights drop, and watered less in December than in July. This page is that year, for a live orange or calamondin you already have. It does not rank the listings. The orange tree comparison does that.
Our top picks
| Badge | Product | Named plant | Pot | Winter position | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Carbeth Plants Carbeth mini orange with hessian wrap | Calamondin | 12 cm | Kitchen or conservatory | 8.4 | about £28.99 | View offer |
 Carbeth Plants Carbeth calamondin mini orange | Calamondin | 12 cm | Cooler months indoors | 9.4 | about £27.99 | View offer | |
| Best value |  Plants4Presents Plants4Presents dwarf orange tree | Not named | 1 litre | Cool sunny sill | 8.6 | about £24.79 | View offer |
On this page
The year in a pot
Bring the pot inside when nights start to dip, not when the compost has already frozen. The RHS puts calamondin at a night minimum of at least 13°C, in the light. In summer, after the risk of frost has passed, you can move it outside. The Citrus Centre keeps its glasshouse only just frost-free, around 4°C. That floor and the RHS 13°C line are not the same instruction. Use 13°C at night for a calamondin unless your label says otherwise. If the parcel has not arrived yet, use the orange tree buying guide.
Compost, water and feed
Repot into a peat-free loam-based compost with grit added, and only one step up from the pot it arrived in. The RHS says not to jump a pot size. Water freely while the plant is in growth. In winter, water sparingly. Never leave the pot standing in a saucer of water. The growing guide uses a higher-nitrogen summer feed from late March to October, then a balanced winter feed from November to mid-March. Follow the pack you bought, and do not run both calendars at once. Unflued paraffin or gas heaters in a closed conservatory can scorch citrus leaves. The Citrus Centre warns on that specifically.
When the leaves drop
Leaf drop is the usual winter complaint, and it is usually culture, not a mystery disease. The RHS lists draughts, a winter temperature that is too low or too high, and too much winter water, often together. The RHS calamondin line is at least 13°C. The Citrus Centre overwinters near 4°C. BBC Gardeners' World has said a potted calamondin can cope down towards −5°C and still wants the pot brought in. For a mail-order calamondin, follow 13°C at night unless your label is more specific. A sweet orange is a different plant, set out on calamondin or sweet orange.
Pests and the point you stop
After the watering and the temperature are plausible, look at the leaves you have left. Sticky residue, sooty mould, or small brown scales along the midrib are the usual indoor citrus pests: scale and mealybug. They often arrive already on a posted plant, which is why you photograph the foliage on day one. BBC Gardeners' World suggests washing sticky leaves with a soapy solution and, under glass, considering biological controls. Call a vet if a pet chews the plant and then vomits. Do not call citrus pet-safe.
Common questions
When do I bring an orange tree inside?
Bring it in when nights begin to fall, before a frost sits on the pot. The RHS describes citrus as a plant you move under cover for a British winter, then harden off again in late spring, sometimes not outside until mid-June. Waiting until the compost has frozen is already late. A fleece on the patio is not a substitute for a bright room.
How warm does a calamondin need to be at night?
The RHS figure to follow is at least 13°C, in the light. You will also see about 4°C from the Citrus Centre's frost-free glasshouse, about 10°C in other nursery copy, and a BBC line that mentions down towards −5°C for a pot that is still brought in. Those are not one fact. Use 13°C for a calamondin unless the label on your plant says something clearer.
How often do I water in December?
Less than in summer, and never on a timer you set in July. The RHS says water sparingly in winter and freely in growth, and never leave the pot in water. Feel the compost. If it is still damp from last week, leave it. Rainwater is better when you have it. A radiator shelf dries the pot faster and is still the wrong place, because the air is hot.
What feed should I use, and when does it change?
Use a citrus feed, not a general tomato feed you happen to have open, unless the pack is actually for citrus. The RHS growing guide runs a higher-nitrogen summer feed from late March to October and a balanced winter feed from November to mid-March. The problems page mentions a mid-summer switch. Follow the pack in your hand rather than mixing both calendars.
Why have the leaves fallen off?
Usually a draught, a winter that is too cold or too hot, or too much water in the dark months, often combined. Citrus is not deciduous, so a bare plant in November is a problem, not a season. Check whether the compost is sodden or bone dry, and whether the pot is over a radiator or in a cold corridor. A green stem can leaf again. A plant that arrived already bare is a seller conversation, with photos.
Can I repot it into a much bigger tub the day it arrives?
No. Move one pot size at a time, into peat-free loam-based compost with grit. A wide tub around a small root ball stays wet and is a common way to lose a mailed citrus. If the plant is already dropping leaves, sort water and temperature before you repot at all.
Do the flowers need hand-pollinating?
No. The RHS problems guidance is that citrus flowers do not need an artificial pollination routine to set fruit. You can still enjoy the scent. Poor fruit set is more often light, feed or a plant that is simply too young than a lack of a paintbrush. A 12 cm mail-order tree is not a cropping orchard in its first winter.
Related pages
Sources
Public UK sources used for this comparison, last checked in October 2026.
- RHS, How to grow citrus (retrieved October 2026)
- RHS, Citrus × microcarpa (retrieved October 2026)
- RHS, Citrus problems (retrieved October 2026)
- BBC Gardeners' World, calamondin orange tree (retrieved October 2026)
- Plant Health (England) Order 2015, Schedule 6 (retrieved October 2026)
- GOV.UK, Issuing plant passports (retrieved October 2026)
- Consumer Rights Act 2015, section 9 (retrieved October 2026)
- Which?, Houseplants in the post (retrieved October 2026)