Tree · Malvaceae
American Basswood
Tilia americana
A towering, easygoing shade tree bursting with fragrant summer flowers the bees swarm to.
Full sun
Every 7–14 days
USDA 3–8
60–80 ft · 18.3–24.4 m
Overview
American basswood, the native giant most people call linden, is a shade tree that fully earns its nickname the bee tree. Through late spring and early summer it erupts in small, pale-yellow flowers whose scent rides the breeze, and pollinators swarm it from first light to last. Let it run and it rockets up to a commanding 60 to 80 feet (18 to 24 m) under a broad, rounded crown.
Here is a tree built for the long haul, and it makes the ride easy. It powers through hard winters, thrives in full sun or part shade, and shrugs off soil worries as long as the ground drains. The big heart-shaped leaves throw down a deep, generous shade, and that soft, light wood is the very thing that named basswood and won it a devoted following among carvers.
Plant it somewhere it can stretch and it practically raises itself. Just plan around one quirk: aphids adore it and drizzle sticky honeydew all summer, so give it a thought before you drop a patio or park a car right under the canopy.
Care
The short version: plant it in full sun to part shade in moist, well-drained soil, keep the water coming while it is young, and then let it cruise on its own.
Light
Linden charges ahead in full sun but takes partial shade in stride. Pour on the sun and you get a denser crown and heavier bloom, while a shadier corner still delivers a healthy, if looser, tree.
Water
Keep a young tree evenly moist and water it every 7 to 14 days through dry stretches. Once it establishes it can ride out some drought, but it always powers along better with steady moisture, so never let it bake for weeks on end.
Soil
It stays refreshingly unfussy and takes on clay, loam, or sand, as long as the ground is medium-moisture and well-drained. Any pH from 5.5 to 8.0 keeps it happy, which sweeps in just about any garden soil you have.
Temperature
This tree is a cold-weather champ, cruising anywhere from -40°F to 100°F (-40°C to 38°C). It powers through brutal winters and blazing summers alike, which is exactly why it thrives across so much of the country.
Humidity
Outdoor humidity never fazes a linden, so skip chasing a number. Air circulation is the real player, since still, damp air trapped around the canopy is what ushers in leaf spots and mites.
Feeding
An established tree in decent soil barely needs a bite. If growth drags, work in a balanced slow-release tree fertilizer in early spring, but keep it light, since a nitrogen overload just throws a feast for the aphids.
Pruning
Prune in late winter to early spring to drive one strong central leader and clear out dead, damaged, or crossing branches. The tree also fires up basal suckers and sprouts, so snap those off the moment they show.
Repotting
Linden is a landscape powerhouse, not a container plant, so repotting drops off the map once it hits the ground. If a nursery tree shows roots circling the pot or bursting out the drainage holes, get it planted out on the double.
Size & spacing
Hand a linden plenty of room, because it climbs to 60 to 80 feet (18 to 24 m) tall and fans out 30 to 60 feet (9 to 18 m) across. Set it well clear of buildings, walls, and overhead lines so that wide crown can throw itself open.
When to plant
Good news for the impatient: linden is a tree, so there is no annual sowing season to chase. Set young trees out in spring or fall, once the hard frosts clear, and the fragrant flowers roll in on their own from late spring into midsummer.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: Spring or fall, after the threat of hard frost has passed
- Harvest: Fragrant pale-yellow flowers in late spring to early summer (May to July)
Hardiness
USDA hardiness zones: 3–8
Temperature: down to -40°C
Troubleshooting
A healthy linden mostly runs the show itself, and most of what pops up is purely cosmetic. Match the signs below before you grab any treatment, since a big tree brushes off pests that would rattle a smaller plant.
Wilting limbs, sawdust, and round holes low on the trunk
The linden borer bores its way through the wood of the lower trunk and limbs, tipping you off with round exit holes and sawdust-like frass right where it works. Cut out any limb it has claimed and destroy it fast. Borers zero in on stressed trees, so keep yours watered and full of vigor, guard the bark from mower and trimmer scrapes, and rope in an arborist if the trunk takes a hit.
Fix:
- Prune out and destroy borer-infested limbs
- Keep the tree vigorous, as borers preferentially attack stressed trees
- Consult an extension office or arborist for severe trunk infestations
Shiny, sticky leaves with a dark film chasing them
That glossy sticky stuff is aphid honeydew, and the black that trails it is just a harmless sooty mold cashing in on the sugar. Big aphid crowds, sometimes with scale insects piling on, rain the residue down over everything below. Blast them off with a sharp jet of water, cheer on the lady beetles and lacewings that come to feast, and the film clears the moment the honeydew dries up.
Fix:
- Hose aphids off with a strong jet of water
- Encourage beneficial predators such as lady beetles and lacewings
- Apply insecticidal soap or horticultural oil to accessible foliage for severe infestations
- Sooty mold disappears on its own once the honeydew source is controlled
Summer leaves gnawed down to lacy skeletons
Japanese beetles are the culprits, chewing out the soft tissue and leaving the veins to hang like lace from June to August. On a young tree, march out at dawn and knock those shiny green beetles into soapy water while they are still sluggish. A big, established linden bounces right back and pushes fresh leaves, so ditch the pheromone traps that just call in more of the crowd.
Fix:
- Hand-pick or knock beetles into soapy water in the early morning on smaller trees
- Tolerate damage on large established trees, which recover
- Avoid Japanese beetle pheromone traps, which attract more beetles
Leaves turning stippled, spotted, or browned
A handful of small troublemakers can leave the foliage looking rough. Lace bugs, basswood thrips, or spider mites stipple the leaves and scatter dark fecal specks on the undersides, and fungal leaf spots pop up as clean lesions when the season turns wet. Rake up the fallen leaves to slash the spore load, spray the canopy in dry spells to send the mites packing, and past that just let it ride, since nearly all of it is skin-deep.
Fix:
- Rake and dispose of fallen leaves to reduce fungal spores
- Hose down foliage to dislodge mites in dry spells
- Most leaf spot is cosmetic and needs no treatment
Toxicity
Great news for pet owners: linden is completely safe. The ASPCA lists it as non-toxic to cats, dogs, and horses, and it carries no poisonous compounds anywhere in the tree. The fragrant flowers even dry into a calming tea, and the young leaves are tender enough to eat.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
A curious cat can nibble away here, since the ASPCA marks linden as non-toxic to cats. A giant mouthful of any plant might stir up a passing stomach upset, but this tree packs no poison at all.
Dogs None
Dogs get the all-clear too, because the leaves, bark, and flowers hold nothing toxic. Let one gnaw a fallen branch and it will be just fine.
Horses None
Horses can browse a linden freely without a scrap of harm, and the ASPCA keeps it on the non-toxic list for them. The young leaves and flowers make safe, tasty forage.
Rabbits Safe
Rabbits can munch the leaves and twigs with zero toxic risk. Linden is a go-to browse plant, and that tender spring growth is perfectly safe for them to enjoy.
Livestock Safe
Cattle, goats, and sheep can graze the foliage safely, since the tree carries nothing that would trouble them. Farmers have cut linden for fodder for ages without a single hitch.
Birds Safe
Birds nest up in the canopy and forage around the flowers with no danger whatsoever. The seeds and buds carry no toxic threat either.
People Safe
People are safe with linden as well, and the fragrant flowers dry into a soothing tea while the young leaves are tender enough to eat. Nothing on this tree needs steering clear of.
No special handling precautions; honeydew from aphids can make surfaces under the tree sticky but is not toxic.
Varieties
A few linden forms are well worth chasing down, from compact native picks to silver-leaved cousins. These are the ones that show up most in yards and along the street.
Tilia americana 'Redmond'
A tighter, more pyramidal spin on the native tree that caps out near 40 to 60 feet, which is exactly why it wins spots as formal shade and along streets.
Tilia cordata 'Greenspire'
A littleleaf linden dressed in small heart-shaped leaves of 1 to 3 inches under a dense oval crown, prized as a tough, city-proof street tree clear across Europe and beyond.
Tilia tomentosa
The silver linden flips its dark green leaves in the breeze to flash white woolly undersides, setting the whole tree shimmering.
How to propagate
There are several fun ways to launch a linden depending on your goal, from slow-burn seed to grafting for named cultivars to the suckers the tree tosses up for free.
SeedDemanding
Sow cleaned seed outdoors in fall, or stratify for sowing in spring · 1-2 years or more to germinate
Raising linden from seed is a genuine test of grit. The seeds pack a hard coat and a double dormancy, so even after warm-then-cold stratification they can hang on for one to two years before they finally break, then rise slow and patchy. Sow cleaned seed outdoors in fall, or stratify it for a spring sowing, and settle in for the long game.
GraftingDemanding
Late winter for bench grafting or summer for budding · 1 growing season to take
Named cultivars like 'Redmond' and 'Greenspire' refuse to come true from seed, so growers graft or bud them onto seedling rootstock to lock in the form. Bench graft in late winter or bud in summer, and a solid union knits together across a single growing season.
LayeringModerate
Spring · 1-2 years to root
Basswood keeps pushing up sprouts and suckers from its base all on its own, handing you a ready-made clone to run with. In spring, pin a low branch to the ground to layer it, or lift a rooted sucker, then give it one to two years to grow a root system of its own before you move it.
Myths
Linden trees are poisonous to dogs and cats.
Not a chance, since the ASPCA lists linden as non-toxic to dogs, cats, and horses, with nothing toxic in any part of the tree. A pet that gobbles down a lot of any plant might land a mild stomachache, but there is nothing poisonous about a linden.
The sticky black coating on basswood leaves is a disease that is killing the tree.
The film is just aphid honeydew, with a harmless sooty mold cashing in on the sugars. It looks dramatic, sure, but it is purely cosmetic, and it clears itself once the aphids are dealt with. An established tree never takes a hit from it.