Tree · Sapindaceae
Sugar Maple
Acer saccharum
With rich, evenly moist soil and space to stretch out, a sugar maple settles in and gives back generous shade and bright autumn leaves.
Full sun
Every 7–14 days
USDA 3–8
39–79 ft · 12–24 m
Overview
If you have ever loved a New England autumn or poured real maple syrup, you already know the sugar maple. It takes its time, growing into a broad, rounded shade tree that can reach 80 feet (24 m), carried on a stout trunk beneath a full canopy that keeps things cool all summer. When fall arrives the leaves warm into orange, red, and gold, and that glow is the reason most people welcome one into the yard.
This is a tree that loves cold country, so do not fret about hard winters. It is happy in zones 3 through 8 and takes cold down to -40°F (-40°C) without complaint, though it has little patience for the heat, road salt, and packed soil of a tight city lot. Give it deep, fertile, evenly moist ground with plenty of room for the roots, and it will settle in and do well for generations.
Patience is really all this tree asks of you. Sugar maple grows slowly and lives a long time, so you are planting it for the decades ahead and for whoever enjoys the yard after you. In late winter its sap turns sweet, and that is why sugarhouses across the north tap it each spring to boil down maple syrup.
Care
The short version: plant it in full sun to part shade in deep, fertile, evenly moist but well-drained soil, water about an inch a week when heat or drought sets in, and keep it well clear of pavement and road salt, and it will forgive the rest.
Light
Sugar maple is happiest in full sun and handles partial shade with ease, especially while it is young. More sun brings fuller fall color and a thicker crown, but even a half day of light will raise a healthy, contented tree.
Water
Keep the soil deep and evenly moist, watering roughly every 7 to 14 days whenever rain runs short. In real heat or a dry spell, give an established tree about an inch of water a week, which is the easy way to head off the leaf scorch this species can get.
Soil
Plant it in deep, fertile loam that stays moist yet drains freely and holds plenty of organic matter. A pH from 5.5 to 7.0, slightly acidic to neutral, suits it well, and the one thing it will not accept is compacted, soggy ground.
Temperature
This is a genuinely cold-hardy tree, at home anywhere from -40°F to 95°F (-40°C to 35°C). It shines in the north and has a harder time where summers stretch long and hot.
Humidity
Ordinary outdoor air is all it needs, so there is no humidity level to chase. Good airflow and steady soil moisture matter far more to its health than anything in the air around it.
Feeding
Feed in early spring with a balanced slow-release tree fertilizer, and let a simple soil test tell you how much it truly needs. A ring of mulch laid around the drip line will feed the roots gently as it breaks down.
Pruning
Prune only in summer or full dormancy to take out dead, damaged, or crossing limbs, since a maple cut in late winter or early spring bleeds sap heavily. Wipe your tools between cuts with 10 percent bleach or 70 percent alcohol so no disease travels from one branch to the next.
Repotting
Sugar maple is a landscape tree rather than a container plant, so repotting rarely comes into it. Just keep an eye on nursery or potted stock for roots circling the trunk flare or a top that lags behind a crowded root ball, and loosen those roots gently before planting.
Size & spacing
Give this tree honest room to grow. It climbs to 40 to 80 feet (12 to 24 m) tall and spreads 30 to 60 feet (9 to 18 m) across, so plant it well clear of the house, the driveway, and any power lines.
When to plant
Set a sugar maple in the ground in spring or fall, while the weather stays cool and the roots can get comfortable before any stress. The small greenish-yellow flowers open in April, just before or alongside the leaves, and the real reward waits until autumn, when the whole canopy turns to red, orange, and gold.
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: Inconspicuous greenish-yellow flowers in April before or with the leaves; brilliant red, orange, and yellow fall color
Hardiness
USDA hardiness zones: 3–8
Temperature: down to -40°C
Troubleshooting
Most sugar maple worries show up on the leaves first, whether the cause is heat, a soil fungus, or a soggy spring. Once you learn to read those signs you can tell a harmless blemish from something that needs real attention, so match what you see below before you reach for any spray.
One limb or side fading while the rest looks fine
If a single limb or one whole side of the tree fades while everything else looks healthy, the likely cause is Verticillium wilt, a soil fungus that clogs the water channels inside the wood. Peel a little bark from a wilting branch and look for green or brown streaks, then send a sample to a lab, since most maple diseases look alike to the eye. There is no cure, so take out the dead wood as it appears and keep the tree watered and fed to give it as many good years as possible.
Fix:
- There is no cure; prune out dead branches as they appear
- Water about one inch per week and fertilize based on a soil test to prolong tree life
- Mulch around the drip line and sanitize pruning tools with 10 percent bleach or 70 percent alcohol between cuts
Scorched brown leaf edges during summer heat
When the leaf edges and the strips between the veins turn brown in a hot, dry stretch, you are seeing leaf scorch, which simply means the roots cannot pull up water fast enough to keep the leaves supplied. Salty soil, compaction, or a cramped root zone near pavement all make it worse. Water an established tree with about an inch a week through heat and drought, and lay mulch over the roots to hold onto the moisture that is already there.
Fix:
- Water established trees with about one inch of irrigation per week during heat and drought
- Mulch over the root zone to conserve moisture and moderate soil temperature
- Avoid salt accumulation and soil contaminants around the roots
Shiny black spots ringed with yellow in late summer
Those thick, glossy black blotches circled with yellow are tar spot, a leaf fungus that looks worse than it is and does little lasting harm. Rake up and get rid of the fallen leaves each autumn, since that is where the fungus waits to start over. On a small tree a copper fungicide at leaf-out is an option, though for most maples it simply is not worth the bother.
Fix:
- Rake up and destroy fallen leaves where the fungus overwinters
- If desired on small trees, apply a copper-based fungicide, mancozeb, or triadimefon three times at two-week intervals starting at spring leaf unfurl
Browned leaves and dead buds following a wet spring
A long, cool, wet spring can bring on anthracnose, a fungus that browns the leaves along their veins, kills the buds, and leaves behind crooked twig dieback. Rake up and destroy the infected leaves so the spores cannot carry into next year. Better airflow and foliage that dries quickly keep it from getting a foothold to begin with.
Fix:
- Rake and destroy fallen infected leaves
- On valuable small trees, spray a copper-based fungicide, mancozeb, or chlorothalonil three times at two-week intervals from spring leaf emergence
Toxicity
You can relax about this one. Sugar maple is safe for people, pets, and livestock, and its boiled-down sap is the very syrup that ends up on your pancakes. The wilted-leaf poisoning that frightens horse owners traces back to red and silver maple, not to this tree.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Cats are safe here. A curious one that chews on a fallen leaf will come to no harm from this tree.
Dogs None
Dogs have nothing to worry about. Nothing in the leaves, bark, or twigs will upset them.
Horses None
Horses are fine around sugar maple. The well-known red-blood-cell poisoning comes from the wilted leaves of red maple and silver maple, not from this tree.
Rabbits None
Rabbits can nibble the leaves without any trouble.
Livestock None
Cattle, goats, and sheep can graze around sugar maples with nothing to fear.
Birds None
Birds nest and feed safely up in the canopy, and the seeds help feed plenty of other wildlife too.
People None
People are safe with it. Boil the sap down and you get maple syrup, so a bit of this tree ends up right on your breakfast table.
Non-toxic to cats and dogs. Note that it is the related red maple (Acer rubrum) whose wilted leaves are notoriously toxic to horses; sugar maple is not the species classically implicated, but as a general precaution wilted maple leaves of any species are best kept away from horses.
Varieties
Most sugar maples sold for the yard are named selections chosen for sturdier leaves and brighter fall color, and any of them makes a fine, forgiving choice. These are the ones worth asking for by name.
Green Mountain
Bred to take heat and drought, it carries a dense oval crown and glows orange-red once fall arrives.
Legacy
A strong, scorch-resistant selection whose thick, glossy leaves stand up well to tearing and dry spells.
Fall Fiesta
A rugged, quick-to-settle tree loved for its reliable yellow-orange to red fall color and leaves that linger later than most.
How to propagate
You can raise a sugar maple from seed with a bit of cold treatment, and it is a rewarding little project. Just know that the named selections only stay true to type when they are grafted.
SeedModerate
Sow outdoors in fall or after 60-90 days of cold, moist stratification before spring sowing · 1 to 2 growing seasons
Sugar maple seed will not wake up until it has felt a cold spell, so either sow it outdoors in fall or give it 60 to 90 days of cold, moist stratification before sowing in spring. A young tree usually finds its feet over 1 to 2 growing seasons, so a little patience pays off. You can also start the species from layering or from stem cuttings.
GraftingDemanding
Late winter (bench graft) or summer (budding) · 1 to 2 seasons
Named selections such as Green Mountain and Legacy will not come true from seed, so growers graft or bud them onto seedling rootstock instead. Bench grafting happens in late winter and budding in summer, and the union usually knits together over 1 to 2 seasons. It does take a steady, practiced hand, which is why this counts as the demanding route.
Myths
Every maple, sugar maple included, is deadly to horses.
The real risk lies with red maple and silver maple, whose wilted leaves can destroy a horse's red blood cells. Sugar maple is not the guilty party, and rather than being poisonous it is the very tree tapped for maple syrup.