Tree · Rutaceae
Lemon
Citrus limon
Give it full sun, deep but occasional water, and a little frost protection, and your lemon tree will reward you with fruit for years.
Full sun
Every 7–14 days
USDA 9–11
6–20 ft · 1.8–6 m
Overview
The lemon is a small evergreen tree in the citrus family, and it's a lovely one to grow, with glossy leaves, sweetly scented white blossoms, and cheerful tart yellow fruit. It made its way from Asia through the Mediterranean and settles happily wherever winters stay mild, in zones 9 to 11. Find it a warm, sunny corner and you may be delighted to see flowers and fruit on the tree together, sometimes right through the year.
You have room for a lemon whether you plant it in the ground in a frost-free spot or keep it in a big pot you can wheel under cover when the cold rolls in. A grown tree reaches 6 to 20 feet (1.8 to 6 m) tall, and don't worry if space is tight, because dwarf types stay much smaller and are perfect for a patio or sunroom. Nearly every tree you'll buy is grafted onto a hardy rootstock, which is simply why a lemon grown from a pip rarely takes after its parent.
Give a lemon what it likes and it asks very little of you in return, so a first tree is nothing to be nervous about. The main things to watch are frost, soggy roots, and a short list of citrus pests and diseases, all of them manageable. Get the drainage and the watering rhythm comfortable, keep an eye on the tender new growth, and your tree will keep fruiting for many happy years.
Care
The short version: give it full sun and shelter from frost, water deeply only once the top few centimetres of soil have dried, use well-drained soil rich in organic matter, and offer a monthly citrus feed through the growing season, and you're set.
Light
Your lemon will love full sun, ideally 8 hours or more a day, since that's what fuels all those flowers and fruit. It will get by on partial sun or bright indirect light indoors, but expect a leggier tree and a lighter crop when the light drops off.
Water
Water deeply, then simply wait until the top few centimetres of soil dry out before you water again, usually every 7 to 14 days. Citrus dislike both drought and soggy roots, so the rhythm matters far more than the exact amount. A potted tree dries faster, so check it a little more often when the heat is up.
Soil
Settle your tree into well-drained sandy loam with plenty of organic matter, and never let the roots stand in water. A slightly acidic pH of 5.5 to 6.5 helps it take up nutrients nicely. Drainage really is the one thing a lemon won't forgive, so get that right and you're golden.
Temperature
Lemons are at their best in warmth, coping across roughly 28°F to 100°F (-2°C to 38°C), though frost near that low end nips the tender growth. Keep a potted tree above freezing over winter and it will come through just fine.
Humidity
Average humidity of 30% to 60% suits a lemon perfectly, so this is truly nothing to fuss over. Indoors, the only thing to watch is the dry air near a heater, where an occasional misting or a pebble tray does the trick.
Feeding
Feed once a month through the growing season, from spring into late summer, with a citrus-specific fertilizer higher in nitrogen. The extra iron, zinc, and manganese quietly head off the yellowing that citrus can be prone to.
Pruning
Lemons ask for very little shaping, which takes the pressure off. Prune lightly in late winter or early spring to take out dead, crossing, or weak wood and any suckers below the graft union, then thin the canopy just enough to let light and air move through.
Repotting
Shift a container tree into a pot one size larger every 2 to 3 years. Roots circling the pot, water rushing straight through, or growth that stalls even though you're feeding all gently tell you it's time to size up.
Size & spacing
A lemon tree grows 6 to 20 feet (1.8 to 6 m) tall with a spread of 5 to 15 feet (1.5 to 4.5 m), so give it open room to stretch, or pick a dwarf for a snug corner or a container.
When to plant
A lemon lives on warmth and simply stops at frost, so timing is on your side once it turns mild. Set young trees out in spring after the cold has passed and the soil has warmed. Blossom arrives mostly in spring, and the fruit takes its own sweet time, ripening roughly 6 to 9 months later with peaks that often land in winter.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: spring, after all danger of frost has passed and soil has warmed
- Harvest: Blooms mainly in spring but is everbearing in mild climates; fruit ripens roughly 6 to 9 months after bloom, with peaks often in winter. Trees are typically grafted onto rootstock rather than grown from seed.
Hardiness
USDA hardiness zones: 9–11
Temperature: down to -7°C
Troubleshooting
Most lemon worries turn up on the leaves first, whether a pest is mining the new flush or a fungus is blistering the older foliage, and that's actually good news for you. Learn to read those early signs and you can step in gently before the tree slips. Match what you're seeing below, then handle it while your help still counts.
Patchy mottled leaves, dying twigs, and lopsided bitter fruit
This one is serious, so it helps to know the signs of Huanglongbing, also called citrus greening, a bacterial disease that the Asian citrus psyllid carries and that slowly takes a tree down. There is sadly no cure, and a confirmed tree needs to come out so the trees near it stay safe. The blotchy mottling spills unevenly across the veins, which tells it apart from a neat nutrient shortage, and anything you suspect should go straight to your agricultural agency for testing.
Fix:
- There is no cure; remove and dispose of confirmed infected trees to protect the area
- Report suspected cases to your state department of agriculture or extension office
- Manage the Asian citrus psyllid vector
Sticky film, black soot, and little bumps on the stems
Those tiny fixed bumps are scale insects sipping sap, and the sticky sheen with black mold is simply the honeydew they drip behind them. Don't worry, a light run wipes or prunes away easily, and a narrow-range horticultural oil covers the rest so it clears up. Gently discourage any ants as well, since they tend the scale and shoo off the helpful predators that would otherwise tidy things for you.
Fix:
- Wipe or prune off light infestations
- Apply horticultural or narrow-range oil for thorough coverage
- Control ants to allow natural predators and parasitoids to work
Greasy yellow-brown blisters underneath the older leaves
This is greasy spot, a fungus that raises blisters on the undersides of older leaves after warm, muggy spells and slowly loosens them from the tree. The kind fix is simple: rake up and bin the dropped leaves where the spores wait out winter, and open the canopy with a little pruning so the foliage dries sooner. A copper or oil spray timed to the summer flush lends a hand where it's advised for your region.
Fix:
- Rake and remove fallen leaves that harbor spores
- Improve airflow through pruning
- Apply a copper or horticultural oil spray timed to summer leaf flush where recommended
Silvery squiggles and curling on the fresh new leaves
If you spot silvery trails snaking through the youngest leaves, take heart, because this is only the citrus leafminer feeding inside that tender flush. Pinch away the worst leaves and ease back on nitrogen and light trimming, since both invite the soft new growth the larvae seek out. On a settled tree it looks worse than it is and seldom touches your harvest, so you can relax and let a gentle approach do the work.
Fix:
- Prune off and dispose of heavily mined new flush
- Avoid excess nitrogen and frequent light pruning that forces vulnerable new flush
- Use horticultural oil on new growth; protect natural parasitoid wasps by avoiding broad-spectrum insecticides
Toxicity
Here's the reassuring part: the flesh and juice are safe for people, so your kitchen is in the clear. The rest of the tree is another matter, since the peel, leaves, and seeds hold essential oils and psoralens that the ASPCA flags as toxic to cats and dogs, and those same compounds can upset other animals. Just keep rinds, prunings, and any concentrated citrus oils away from your pets and everyone stays happy.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds
Safe for
People
Cats Mild
A cat who nibbles the peel or leaves will usually get an upset tummy, loose stools, drooling, and a low, listless mood, and it tends to pass on its own. Be aware that concentrated citrus oil on the fur can also leave the skin touchy in sunlight.
Dogs Mild
A dog that gnaws bark, leaves, or peel is likely to feel queasy, with diarrhea and a dip in energy for a while. Strong citrus oils can make the skin flare in sunshine too, so keep those products off your dog and you'll both be fine.
Horses Mild
The same oils and psoralens in the peel and leaves can unsettle a horse's gut and leave it a little dull. Happily, most horses turn up their nose at the bitter foliage, so real trouble is rare.
Rabbits Caution
A rabbit's delicate digestion doesn't get along with the fragrant oils in the peel and leaves. Skip the rind and greenery altogether, and think of even a scrap of the juicy flesh as a rare little treat.
Livestock Caution
Cattle, goats, and sheep hardly ever bother with citrus, though the oily peel and leaves can irritate the stomach if they nibble. To stay on the safe side, keep prunings and fallen fruit out of the grazing area.
Birds Caution
It's best to keep the concentrated oils in the rind and leaves well away from pet birds, whose bodies cope poorly with those compounds. A tiny taste of the plain flesh is truly the most they should ever get.
People Flesh safe
Good news for the cook: the flesh and juice are everyday kitchen favorites and perfectly safe to eat and drink. Working with a lot of peel or oil can leave your skin sensitive to sun, so give your hands a rinse before you step outside.
Keep peels, leaves, seeds, and any concentrated lemon essential oils away from pets, and avoid applying citrus oil products to animals.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
Poison Control: (800) 222-1222
Canada
Poison Centres: 1-844-764-7669
Varieties
There are hundreds of lemon selections out there, but only a handful turn up in nearly every garden and grocery aisle. These are the friendly few worth knowing by name.
Eureka
This is the everyday lemon you know from the store, near enough thornless and happy to fruit right through the year where winters stay mild.
Lisbon
A strong, thorny grower that gives you heavy crops in seasonal bursts and copes with both cold and heat more gracefully than Eureka.
Meyer
A gentle lemon-mandarin cross whose sweeter, less sour fruit and thin orange-tinged rind make it a much-loved dwarf tree for pots.
How to propagate
Lemons are almost always multiplied by grafting, though you're welcome to try a cutting or sow a seed as well, as long as you're happy with the trade-offs each path brings.
GraftingDemanding
Active growing season, late spring to summer · A season or more for the graft to take and push growth
Grafting is how the pros do it, budding a chosen lemon scion onto a tough, disease-resistant rootstock during the active growing season from late spring into summer. It does take a steady hand, and the graft wants a season or more to knit together and start pushing new growth, but your reward is a tree that fruits true and carries the rootstock's hardiness.
Stem cuttingsModerate
Spring to early summer from semi-hardwood growth · Several weeks to a few months to root
You can absolutely root a lemon from semi-hardwood cuttings taken in spring or early summer, and they usually strike in anywhere from several weeks to a few months. The tree then grows on its own roots, which feels simpler than grafting, though it does give up the disease resistance and vigor a good rootstock would have offered.
SeedModerate
Sow fresh seed from ripe fruit · Many years to reach fruiting size, if ever true to type
Sowing fresh seed from ripe fruit is easy and fun to try, just know the seedlings come up variable, often thorny, and take many years to reach fruiting size, if they ever fruit true to the parent at all. That's why seed mostly serves breeding work and rootstock raising rather than a tree you're counting on for harvest.
Myths
A supermarket lemon seed will grow into the very same lemon tree.
The lemons you buy are grafted onto their own rootstock for disease resistance and dependable fruit, so a seedling simply can't copy its parent. What sprouts instead is a slow, unpredictable, often thorny tree that may never fruit the way you were hoping, and that's nobody's fault.
Lemon plants and their oils are perfectly fine around cats and dogs.
The ASPCA actually lists Citrus limon as toxic to cats and dogs, because of the limonene, linalool, and psoralens tucked into the peel, leaves, and seeds. The kind thing is to keep the rind, foliage, and any concentrated citrus oils safely out of a pet's reach.