Kumquat
Fortunella
Fortunella
This group is more cold-tolerant than other citrus, but it's the combination of cold and wet that causes losses in the UK, not cold alone — keep roots on the dry side if caught out by an early frost, and still bring it under cover for winter rather than relying on its extra hardiness alone.
Care
The brightest spot available — ideally outdoors in a sheltered, sunny spot for summer.
Keep compost consistently moist in the growing season, allowing the top to dry slightly between waterings in winter.
Free-draining, citrus-specific peat-free compost. Citrus need a specialist balanced feed with trace elements, not a generic houseplant feed.
Prune lightly in spring to shape and remove any dead or crossing growth; remove any fruit that drops prematurely.
Citrus are fed all year, but with two different formulas: a nitrogen-rich summer citrus feed during active growth, and the low-nitrogen winter formula while the plant is cool and resting. Using the summer feed in winter is the classic cause of yellowing, dropping leaves.
Semi-ripe cuttings in summer, with bottom heat. Be aware that shop plants are grafted for vigour and disease resistance, so a plant on its own roots will be slower and may take years to fruit; seed does not come true at all.
Month by month
Months change with the climate: in southern Italy tomatoes go out two months earlier than in England.
- MarchStart a specialist citrus feed as growth resumes in spring. how ›
- JuneMove outdoors to a sheltered, sunny spot once frost risk has passed. how ›
- OctoberBring back under cover before the first frost — this group tolerates an occasional brief light frost better than other citrus once mature, but a reliable winter shelter routine is still what keeps it healthy in the UK. how ›
Months based on climate: UK. Your choice stays on this device.
- MarchStart a specialist citrus feed as growth resumes in spring. how ›
- MayMove outdoors to a sheltered, sunny spot once frost risk has passed. how ›
- OctoberBring back under cover before the first frost — this group tolerates an occasional brief light frost better than other citrus once mature, but a reliable winter shelter routine is still what keeps it healthy in the UK. how ›
Months based on climate: Northern Italy. Your choice stays on this device.
- FebruaryStart a specialist citrus feed as growth resumes in spring. how ›
- MayMove outdoors to a sheltered, sunny spot once frost risk has passed. how ›
- NovemberBring back under cover before the first frost — this group tolerates an occasional brief light frost better than other citrus once mature, but a reliable winter shelter routine is still what keeps it healthy in the UK. how ›
Months based on climate: Central Italy. Your choice stays on this device.
- FebruaryStart a specialist citrus feed as growth resumes in spring. how ›
- AprilMove outdoors to a sheltered, sunny spot once frost risk has passed. how ›
- NovemberBring back under cover before the first frost — this group tolerates an occasional brief light frost better than other citrus once mature, but a reliable winter shelter routine is still what keeps it healthy in the UK. how ›
Months based on climate: Southern Italy and islands. Your choice stays on this device.
Common problems
How to spot it. Sudden leaf loss.
What to do. A common, usually temporary stress response — keep moves gradual.
How to spot it. Often a nutrient deficiency.
What to do. Feed with a citrus-specific feed containing trace elements.
How to spot it. Especially on plants kept indoors over winter.
What to do. Treat if noticed.
LemonOrange, Lime
Lemon
Introduce a new citrus plant to full outdoor summer sun gradually, over a week or two, rather than moving it straight from a shop shelf into blazing sun. Lime and citron are the most frost-tender within this group.
Care
The brightest spot available — ideally outdoors in a sheltered, sunny spot for summer.
Keep compost consistently moist in the growing season, allowing the top to dry slightly between waterings in winter.
Free-draining, citrus-specific peat-free compost. Citrus need a specialist balanced feed with trace elements, not a generic houseplant feed.
Prune lightly in spring to shape and remove any dead or crossing growth; remove any fruit that drops prematurely.
Feed all year with a proper citrus fertiliser, switching from the summer formula to the low-nitrogen winter one when the plant comes indoors and growth slows. Never feed a pot that has been allowed to go bone dry — water first, feed after.
Semi-ripe cuttings in summer with gentle bottom heat, accepting that they root slowly and fruit late. For a plant you actually want fruit from, a grafted nursery plant is the honest answer.
Month by month
Months change with the climate: in southern Italy tomatoes go out two months earlier than in England.
- MarchStart a specialist citrus feed as growth resumes in spring. how ›
- JuneMove outdoors to a sheltered, sunny spot once frost risk has passed. how ›
- OctoberBring back under cover (conservatory, greenhouse or bright cool room) well before the first frost — this group has essentially no frost tolerance, unlike hardy_kumquat, so don't wait to see if it survives. how ›
Months based on climate: UK. Your choice stays on this device.
- MarchStart a specialist citrus feed as growth resumes in spring. how ›
- MayMove outdoors to a sheltered, sunny spot once frost risk has passed. how ›
- OctoberBring back under cover (conservatory, greenhouse or bright cool room) well before the first frost — this group has essentially no frost tolerance, unlike hardy_kumquat, so don't wait to see if it survives. how ›
Months based on climate: Northern Italy. Your choice stays on this device.
- FebruaryStart a specialist citrus feed as growth resumes in spring. how ›
- MayMove outdoors to a sheltered, sunny spot once frost risk has passed. how ›
- NovemberBring back under cover (conservatory, greenhouse or bright cool room) well before the first frost — this group has essentially no frost tolerance, unlike hardy_kumquat, so don't wait to see if it survives. how ›
Months based on climate: Central Italy. Your choice stays on this device.
- FebruaryStart a specialist citrus feed as growth resumes in spring. how ›
- AprilMove outdoors to a sheltered, sunny spot once frost risk has passed. how ›
- NovemberBring back under cover (conservatory, greenhouse or bright cool room) well before the first frost — this group has essentially no frost tolerance, unlike hardy_kumquat, so don't wait to see if it survives. how ›
Months based on climate: Southern Italy and islands. Your choice stays on this device.
Common problems
How to spot it. Sudden leaf loss.
What to do. A common, usually temporary stress response — keep moves gradual.
How to spot it. Often a nutrient deficiency.
What to do. Feed with a citrus-specific feed containing trace elements.
How to spot it. Especially on plants kept indoors over winter.
What to do. Treat if noticed.
Questions
Kumquat: is it hardy?
Fortunella: H1c: Tender, needs above 5°C. It survives above 5 °C. Lemon: H2: Tender. It survives down to 1 °C.
Can it grow in a pot?
Grown almost exclusively in pots so it can move between outdoor summer and indoor/greenhouse winter positions.
Kumquat: when do you prune it?
Prune lightly in spring to shape and remove any dead or crossing growth; remove any fruit that drops prematurely.
Kumquat: when does it flower?
In the climate of UK it flowers in April–May.
When do you feed it?
Fortunella: Citrus are fed all year, but with two different formulas: a nitrogen-rich summer citrus feed during active growth, and the low-nitrogen winter formula while the plant is cool and resting. Using the summer feed in winter is the classic cause of yellowing, dropping leaves. Feeding months, UK: January–December. Lemon: Feed all year with a proper citrus fertiliser, switching from the summer formula to the low-nitrogen winter one when the plant comes indoors and growth slows. Never feed a pot that has been allowed to go bone dry — water first, feed after. Feeding months, UK: January–December.