Blue spruce Plant Care

Blue spruce (Picea pungens) belongs to the Pinaceae family within the Picea genus. Blue spruce is native to North America in Arizona, Colorado, Idaho, New Mexico, Utah and Wyoming. Blue spruce is also known as Colorado blue spruce, Silver spruce.

Blue spruce displays a pyramidal, conical tree growth habit, reaching up to 100 ft tall with a spread of approximately 30 ft. Blue spruce produces picea trees produce small, inconspicuous flowers.

Leaf size: approximately 1 inches.

Water a young or newly planted Blue spruce every 7–14 days, soaking the whole root zone, until it is established — usually one to two growing seasons. Established trees mainly need water during long dry spells. In a container, water whenever the top few centimetres of soil are dry.

Blue spruce thrives in full sun to partial shade.

Picea pungens tolerates temperatures of 0–70°F. Blue spruce prefers humidity levels of 40–60%.

Well-draining, acidic soil with good aeration to prevent waterlogging. Good drainage is essential for Blue spruce to prevent waterlogging, which leads to root rot and fungal issues.

Choose a spot with full sun to partial shade and well-draining, acidic soil with good aeration to prevent waterlogging. Avoid low spots where water collects after rain.

Blue spruce is suited to USDA Zone 2a – 7b.

Plant container-grown or balled-and-burlapped trees in spring or early autumn, setting the root flare at soil level, and water well after planting.

Blue spruce can spread to about 30 ft (9.1 m) and reach about 100 ft (30 m) tall. Space plants about 30 ft (9.1 m) apart so mature crowns don't crowd each other, and plant at least half that distance from buildings, fences and paths.

Planning a row or hedge? Try the tree spacing calculator.

Blue spruce needs little pruning. Remove dead, damaged or crossing branches in late winter or early spring.

Don't cut back into old, bare wood: conifers in the pine family rarely sprout new growth from it. To keep a denser shape, trim only the soft new shoots in late spring.

Blue spruce is hardy down to USDA zone 2a, so once established it can stay outdoors through winter in that zone and warmer ones.

Water deeply in late autumn before the ground freezes — evergreens keep losing water through their needles all winter, and spread a 5–8 cm (2–3 in) layer of mulch over the root zone, keeping it away from the trunk.

Young and container-grown trees need extra protection: roots in a pot freeze much more easily than roots in the ground.

A cut Blue spruce stays fresh much longer when it can keep drinking. These steps apply to any cut fir, spruce, Douglas fir or pine.

1. 1. Make a fresh cut

   Saw about 2–3 cm (1 in) off the base of the trunk just before you put the tree in its stand. An old cut seals over with sap within hours and the tree can no longer take up water.

2. 2. Water the stand daily

   Use a stand that holds plenty of water — a common rule of thumb is about 1 litre per 2.5 cm (1 quart per inch) of trunk diameter. Check it every day and never let the level drop below the cut end; a fresh tree drinks the most in its first week. Plain water is enough.

3. 3. Keep it away from heat

   Set the tree well away from fireplaces, radiators, heating vents and sunny windows, which dry the needles quickly. Use low-heat LED lights and switch them off at night and when you leave the house.

4. 4. Take it down when it dries out

   If needles snap instead of bending, or fall in showers when you brush a branch, the tree has dried out and is a fire risk — remove it.

Pets: Pet safety not verified: the ASPCA does not list Blue spruce, so we can't confirm whether it is safe for cats and dogs. If your pet ate a plant, contact your vet or animal poison control.

Blue spruce can be propagated through seeds, grafting. Similar propagation techniques also apply to brewer's spruce plant care, which shares the same genus.

See all plants toxic to cats and plants toxic to dogs.

Blue spruce is susceptible to aphids, spider mites, pine needle scale. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.

Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.

Blue spruce grows outdoors in USDA Zone 2a – 7b. It survives winters down to planting zone 2a. Blue spruce is native to North America in Arizona, Colorado, Idaho, New Mexico, Utah and Wyoming.