Tree · Sapindaceae
Silver Maple
Acer saccharinum
Forgiving and quick to give shade, the silver maple is a friendly first tree that loves damp ground and asks little in return.
Full sun
Every 7–14 days
USDA 3–9
50–80 ft · 15.2–24.4 m
Overview
Do not let the size of a shade tree put you off, because silver maple is one of the most forgiving trees a first-timer can plant. It takes its name from the soft, silvery undersides of its deeply cut leaves, which catch the light and shimmer whenever the wind turns them over. Native to riverbanks and floodplains, it also answers to river, swamp, or water maple, and few shade trees reward your patience with growth this quick.
There is one honest trade-off, and knowing it early keeps you relaxed. Growing fast means the wood comes in weak and brittle, so limbs can crack in ice and strong wind, and the hungry surface roots may lift a sidewalk or press into drains. None of that has to become a headache. Just give the tree plenty of room away from the house, the driveway, and the pipes, and you have already solved most of the problem.
Where this tree makes you look like a natural is on a big, open, damp spot where pickier trees sulk. It shrugs off wet soil, cold winters, and a bit of drought once it settles in, throws down cooling shade fast, and even blooms in late winter while the rest of the yard is still asleep. Plant it with a little care about placement, and you will find it one of the easiest trees to grow.
Care
The short version: give it full sun and moist to wet, slightly acidic soil and it will mostly look after itself. It barely needs feeding, and the one job worth doing is a little structural pruning while the tree is young, so the brittle wood can stand up to storms as it grows. Mistakes here are easy to recover from.
Light
Give it full sun if you can, and you will get the strongest, fullest tree, though it will still take partial shade without sulking. The more sun it soaks up, the thicker the canopy and the nicer the shape, so a bright open spot is a kind choice.
Water
At heart this is a floodplain tree, so it feels right at home in moist to wet ground and even puts up with poorly drained spots. Water young trees regularly until they find their feet, and after that they handle a little drought on their own, so you can relax.
Soil
Silver maple is wonderfully adaptable about soil, happy in anything from average to wet and from well-drained to soggy. It is happiest on the slightly acidic side, a pH of 5.5 to 7.0, and very alkaline ground can leave the leaves looking yellow and washed out, so lean acidic if you have the choice.
Temperature
This is a tough, cold-hardy tree that rides out winters down to -29°F (-34°C) and summers up to 100°F (38°C) without fuss. That wide comfort range is exactly why it grows happily across so much of the country.
Humidity
You do not need to fuss over humidity at all, since ordinary outdoor air suits it perfectly. What the tree really cares about is moisture in the soil, far more than the air around its leaves.
Feeding
A silver maple rarely asks to be fed, so let a soil test guide you before you reach for fertilizer. Use a balanced slow-release tree food in early spring only if the soil shows it is short of something, and on alkaline ground treat any yellowing with iron or manganese instead.
Pruning
If there is one job that truly matters, this is it, and it is not hard. Prune in summer or while the tree is dormant, taking out dead, weak, crossing, or co-dominant stems along with any included bark, and shape young trees early so the brittle wood is far less likely to break when a storm blows through.
Repotting
Because this is a landscape tree, repotting rarely comes up at all. If you are holding a young one in a nursery pot for a while, just move it on before the roots begin circling or poking out of the drainage holes.
Size & spacing
Give it plenty of elbow room and you will both be happier. A grown silver maple reaches 50 to 80 feet (15 to 24 m) tall and spreads 35 to 70 feet (11 to 21 m) wide, so plant it a good distance from buildings, walkways, and any pipes those roots might find.
When to plant
Silver maple feels at home across zones 3 to 9, and you can plant it in either spring or fall while it is dormant or barely waking. Its flowers open early, from February to April, before the leaves even appear, so do not worry if it looks bare and busy at once. Getting a young tree in the ground early gives its roots time to settle before the first hard season.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: Spring or fall
- Harvest: February to April (flowers before leaves)
Hardiness
USDA hardiness zones: 3–9
Temperature: down to -40°C
Troubleshooting
Almost every worry with a silver maple comes back to its fast, brittle growth or to soil that does not quite suit it, and the good news is that early signs are easy to spot. Keep a gentle eye on the limbs and leaves, match what you see to the notes below, and act while it still helps. Most problems are manageable when you catch them soon.
Storm-broken limbs, and how to stay ahead of them
Silver maple puts on height so fast that the wood ends up weak and brittle, and tight V-shaped crotches with bark pinched inside are quick to split under ice, snow, or a strong gust. The kind fix is early guidance, so shape a young tree to one strong leader with wide, open branch angles. Take off any cracked or hanging limbs as soon as you notice them, and for the big ones high overhead, let a certified arborist handle the climb.
Fix:
- Remove broken and hanging limbs promptly
- Make clean cuts back to the branch collar
- Have large or hazardous limbs assessed by a certified arborist
Branches that wilt and die back
If branches wilt suddenly on one side, often with olive streaks hidden in the sapwood, the likely cause is verticillium wilt, a soil fungus that clogs the tree from the inside. In a cool, wet spring anthracnose can also blotch the leaves along their veins. No spray will cure the wilt, so prune the dead wood back well below the trouble, keep the tree watered and strong, and avoid replanting a susceptible tree where wilt has struck before.
Fix:
- Prune out dead wood well below symptoms
- Water during drought and maintain tree vigor
- Do not replant susceptible species in known Verticillium sites
Pale new leaves with green veins
When the newest leaves turn pale and washed out while their veins stay green, the tree is showing chlorosis, which sets in when alkaline soil keeps it from taking up enough manganese or iron. It looks alarming, but it is fixable. Test the soil pH, nudge it lower where you can, work in some chelated iron or manganese, and keep lime away from the root zone so the fresh leaves can green up again.
Fix:
- Test and lower soil pH where feasible
- Apply chelated manganese or iron amendments
- Mulch and avoid lime near the root zone
White fluff on the branches and sticky leaves below
Those soft white lumps clinging to the undersides of the branches are the egg sacs of cottony maple scale, and the sticky honeydew they drip turns into black sooty mold beneath. On a healthy tree the harm is mostly cosmetic, so there is no need to panic. Watch the branches through late spring and early summer, dab the young crawlers with horticultural oil, and let the helpful predator insects carry on their good work.
Fix:
- Apply horticultural oil during dormancy
- Spot-treat crawlers with horticultural oil
- Conserve natural predators and parasitoids
Toxicity
Here is the reassuring part for most homes: silver maple, like all the maples, is non-toxic to cats and dogs, and it is harmless to people, who have long tapped it for a light syrup. The single exception is horses. Wilted or dried maple leaves can harm a horse's red blood cells, so keep fallen and storm-broken foliage well away from any paddock and everyone stays safe.
Toxic to
Horses
Safe for
People · Cats · Dogs · Rabbits · Livestock · Birds
Horses Caution
Fresh leaves on the living tree are fine, but wilted or dried ones are the genuine hazard. A horse that eats them may grow dull and weak, lose interest in food, and pass dark red to brown urine as its red blood cells break down. Gather up storm-downed branches and fallen leaves before they drift into a paddock, and call a vet straight away if a horse has gotten into them.
Cats Safe
Maples sit on the ASPCA non-toxic list, so a cat that samples a leaf has nothing to worry about here.
Dogs Safe
A dog can mouth the foliage or trot off with a fallen twig in the yard, all without any risk of poisoning.
Rabbits Safe
Silver maple gives rabbits no toxicity trouble at all.
Livestock Safe
Cattle, goats, and sheep can graze near a silver maple with no bother, though the same wilted-leaf risk that affects horses is worth keeping in mind for grazing animals.
Birds Safe
Birds happily nest in the canopy and feed on the seeds with no ill effect.
People Safe
The tree is not poisonous to people, and its spring sap has long been tapped for a light, gentle syrup.
Keep wilted, fallen, or storm-downed silver maple leaves and branches away from horses; wilted leaves can cause red blood cell damage (hemolytic anemia) in horses.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
United Kingdom
Animal PoisonLine: 01202 509000 (fee applies)
Australia
Animal Poisons Helpline: 1300 869 738
Varieties
Most silver maples are grown straight from seed, but a couple of named kinds gently smooth over the species' rougher habits. These two are the ones you are most likely to come across.
Silver Queen
It wears a neater oval crown, sets little or no seed for you to rake up, and closes out the season in soft yellow.
Skinneri (Skinner's Cutleaf)
Its deeply cut, lacy leaves and the gentle weeping sweep of its branches make it easy to pick out.
How to propagate
Starting a silver maple is wonderfully easy, mostly because its seed is so eager to sprout. You can raise it from the fresh winged seeds it drops, or, if you want a small challenge, from soft summer cuttings.
SeedEasy
Sow fresh seed in late spring to early summer as soon as samaras ripen · 2 to 4 weeks to germinate; fresh seed germinates readily without stratification
Seed is the friendly way to raise a silver maple. Its winged samaras ripen in late spring to early summer, and since they barely go dormant, the trick is simply to sow them fresh the moment they fall. Planted right away, they sprout in 2 to 4 weeks with no cold treatment needed, which makes early success very likely.
Stem cuttingsModerate
Early summer from softwood · Several weeks to root under mist
If you fancy a little more of a challenge, you can also root softwood cuttings taken in early summer, standing them under mist where they slowly take hold over several weeks. It does work, though the outcome is less certain than seed, so most growers happily start with the samaras.
Myths
Every maple is poisonous to dogs and cats.
The ASPCA places silver maple and its maple cousins on the non-toxic list for both dogs and cats, so a curious pet that nibbles a leaf is in no real danger. The true risk is to horses, and only from wilted or dried leaves, never the green ones still on the tree. Sweep fallen and storm-broken foliage out of any paddock and the worry simply melts away.