Lemon
Citrus limon
Glossy evergreen citrus for a sunny pot — lavender and borage keep its bees.
- Type
- Fruit · Perennial
- Botanical family
- Mixed / other
- Foliage color
- Green
- Flower color
- Yellow
- Sunlight
- Full sun
- Watering
- Moderate
- Soil
- Free-draining, moderately fertile
- Feeding
- Citrus fertilizer every two to four weeks from April through September.
- USDA zones
- 9a–11b
- Frost tolerant
- No
- Flowering
- March
- Pruning
- A light prune in spring: take out dead wood and shape the canopy.
- Overwintering
- Bring it in from October to May, into a bright, cool room at 7–12°C.
- Plant out
- at the last spring frost
- First harvest
- 180 days after the last spring frost
- Harvest ends
- at the first fall frost
- Feb–Mar Bud Break
- Mar–Apr Flowering
- Apr–Nov Fruit Set
- Nov–Dec Harvest
- Dec–Dec Growing
- Jan–Feb Growing
- Plant spacing
- 5 ft 11 in
- In-row spacing
- 4 ft 11 in
- Between rows
- 8 ft 2 in
- Square-foot density
- Not suited to SFG
- Root system
- Woody, shallow and far-reaching
- Working depth
- 12–24 in
- Can reach
- 4 ft down where the soil allows
- Spread
- 16–25 ft across, about 2–3× the width of the plant
Almost all of a tree’s roots are in the top two feet of soil, where the air is, and they run out well past the branch tips. The deep taproot most people picture belongs to the seedling; the tree grows out of it and spends the rest of its life spreading sideways instead.
The habit is Lemon’s own; the figures are what that habit usually comes to at this size, not a measurement of this species. Roots follow the soil either way: a compacted pan, a high water table or heavy clay stops them well short of any of it, and deep open ground lets them go further.
- Cats and dogs
- Recorded toxic
Recorded as toxic to cats and dogs by ASPCA.
We file the lemon as Citrus limon, the ASPCA prints Citrus limonia under the title Lemon. The fruit is edible; the finding concerns the peel and plant material.
- When
- Everbearing in mild climates — a container tree in the UK conservatory can carry flowers and fruit at once, with the main flush ripening in winter; a fruit takes 6–12 months from flower to ripeness. Grafted trees fruit in 2–3 years.
- What to look for
- Full-sized, fully yellow (no green), skin slightly glossy with a little give when squeezed, and fragrant. Citrus ripen only on the tree — no color or sugar develops after picking — but ripe lemons hold on the tree for weeks to months, so the tree is its own store.
- How to harvest
- Cut with secateurs leaving a tiny button of stem, or use a careful twist-and-pull; pulling can tear the skin at the stem end (a "plugged" fruit rots fast). Gloves against thorns on many varieties.
- How often
- Pick as needed — the tree stores them better than your kitchen. Harvest fully colored fruit over weeks or months.
- Storing the crop
- Room temperature 1–2 weeks; refrigerated in a bag, 4–6 weeks. Juice freezes in ice-cube trays; zest freezes; whole lemons preserve famously in salt (preserved lemons) and make curd and marmalade.
- Mealybugs White cottony sap-suckers that gather in leaf axils and along stems, mostly on houseplants and under glass. Dab colonies with a cotton swab dipped in soapy water and isolate affected plants.
- Scale insects Immobile brown or white bumps fixed to stems and leaf undersides, sucking sap and weakening growth. Wipe off with a damp cloth or dab with horticultural soap; watch for the sooty mold that follows.
- Spider mites Red spider mite
- Leaf drop brought on by cold or overwatering
Beneficial predators that hunt this plant's pests — grow their favourite flowers nearby to recruit them. companion plant
- Ladybird (lady beetle) Coccinellidae
The gardener’s favorite ally: adults and their alligator-shaped larvae each eat thousands of aphids, plus scale, mealybugs, and other soft-bodied sap-suckers. Grow flat, open flowers for the adults and never spray a colony that ladybird larvae are already working.
- Green lacewing Chrysoperla carnea
Its bristly larvae — "aphid lions" — impale aphids, mealybugs, thrips, and mite colonies, eating hundreds a week. Adults feed on nectar and pollen from small open flowers and overwinter in hollow stems left standing.
- Hoverfly Syrphidae
Bee-mimicking flies whose legless larvae graze aphid colonies clean while the adults pollinate. A ribbon of shallow, nectar-rich flowers kept in bloom all season recruits wave after wave of them.
- Big-eyed bug Geocoris spp.Hunts Spider mites
A stubby 3 mm bug with enormous wrap-around eyes, working the soil surface and the low foliage for aphids, mites, thrips and insect eggs. It is the main natural check on chinch bugs in a lawn and it is killed outright by insecticide.
- Minute pirate bug Orius spp.Hunts Spider mites
A pinhead-sized true bug that is the best natural check on thrips, and happily spears aphids, mites, and insect eggs too. It needs pollen when prey is scarce, so keep something flowering nearby.
- Predatory mites Phytoseiulus & AmblyseiusHunts Spider mites
Fast orange mites that hunt spider mites egg-by-egg, and cousins that clear thrips and fungus-gnat larvae. Sold as a biological control for greenhouses; outdoors they follow humidity — mist and mulch, don’t dust with sulfur.
- Rove beetle StaphylinidaeHunts Spider mites
Slim, quick beetles with short wing cases that hunt in soil and litter, taking root-fly eggs and larvae, fungus-gnat larvae, and mites. Mulch and undisturbed ground keep them resident year-round.
Basil, Lavender, Marigolds
Good neighbors
A healthy lemon tree can carry flowers, green fruit and ripe lemons all at the same time.
Green-leaved fruit, like this one.
The Cottage Garden Companion — the gardener's herbarium at cottagegardencompanion.com