Read interesting facts about the blue spruce here. Compact facts explain roots, cones and growth per year. Lots of tips about using blue spruce as a Christmas tree.
What are the characteristics of a blue spruce?
The blue spruce (Picea pungens) is an evergreen conifer used as a Christmas tree, windbreak or ornamental tree. It has blue-green needles, shows cones as flowers and fruits and grows 15-40 cm annually. The roots are shallow and the plant is hardy.
Profile
- Scientific name: Picea pungens
- Family: Pine family (Pinaceae)
- Growth type: evergreen conifers
- Synonym: Norway spruce
- Growth: 15 cm to 40 cm per year
- Growth height: 10 m to 35 m
- Leaf: blue-green needles
- Roots: shallow roots
- Flower: cones
- Fruit shape: cones
- Winter hardiness: hardy
- Uses: Christmas tree, firewood, windbreak
Blue spruce growth per year
The annual growth of a blue spruce depends primarily on whether it is the original species in the forest or a variety from the nursery. This growth per year can be expected on average:
- Origin species in Central Europe: 30 cm to 60 cm
- Variety from the nursery: 20 cm to 40 cm
- Dwarf varieties from garden centers or hardware stores: 2 cm to 3 cm
Roots
How do the roots of a blue spruce grow? This is an important question before planting in a pot or bed. All spruce trees have shallow roots. This also applies to Picea pungens and its cultivated forms. However, this property is not associated with any significant risk of wind throw. In fact, the Norway spruce likes to be useful as a windbreak.
Cones
Considering a long life expectancy of several hundred years, the blue spruce takes plenty of time until the first cones dangle from the branches. The first flowering can be expected from the age of 30. Norway spruces are monoecious, segregated conifers. Where and how the cone-shaped flowers and fruits develop depends on gender. Read important details here:
- Female flowers: light pink to light red cones exclusively in the upper crown
- Male flowers: yellowish, reddish cones throughout the entire crown
- Fruit: from August/September brown, later straw-colored cones with a length of 6 cm to 11 cm
In contrast to upright pine cones, the cones of blue spruce trees hang from stable, tiered branches.
Usage
Hobby gardeners like to plant a blue spruce in pots and beds for use as a Christmas tree. Soft spruce wood is less suitable for use as firewood. In contrast to hardwoods such as beech or oak, the calorific value is significantly lower. However, properly stored spruce wood dries in a record time of one year and burns like tinder, so fireplace owners primarily use the wood as kindling.
Planting blue spruce
If you own a blue spruce in a pot, you will have a magnificent Christmas tree ready for use on your balcony and terrace every year. As a solitary plant in the bed, the Norway spruce appears festively decorated at Christmas time. You can find out how to plant a blue spruce correctly in the following sections:
Planting blue spruce in a pot
The blue spruce is planted in a pot whose size allows the root ball two to three finger-widths of space up to the edge of the container. Holes in the bottom act as water drains. Cover the bottom of the pot with drainage made of broken pottery or expanded clay. As a substrate, we recommend high-quality pot plant soil (€18.00 on Amazon) without peat. If you have it on hand, mix in a third of mature leaf compost as an organic starting fertilizer. Ideally, add a few handfuls of expanded clay to optimize permeability.
Water the freshly planted spruce with rainwater until the saucer fills up. Pour away any accumulated irrigation water after 10 minutes to prevent waterlogging.
Planting in the bed
The best time to plant is in autumn. Dig a pit that is more wide than deep. Dimension the excavation so that you can spread the roots in the loose, humus-rich soil without any effort or bends. Press the bed soil down to ensure that the roots are close to the ground without any air holes. Finally, thoroughly muddy the root slice. Drought stress is the most common cause when a planted blue spruce fails to grow.
Location
The following criteria characterize the right location:
- Light: sunny to shady (in partially shaded locations the blue spruce grows irregularly and needles)
- In the pot: two-week acclimatization in a partially shaded location is recommended
- In the bed: plants in nutrient-rich, humus-rich soil, fresh to sandy-dry and permeable
- pH value: acidic to alkaline, ideally 6, 8 to 7, 2
The blue spruce becomes a vagrant when used as a potted Christmas tree. In the bright stairwell or cool-tempered winter garden, you can get the conifer used to the cozy, warm living room for a week. Choose a location that is well away from active radiators. After the holidays, the blue spruce makes another stopover in the stairwell or winter garden.
Excursus
Nordmann fir or blue spruce as a Christmas tree?
Durability, fragrance development and purchase price are the decisive criteria when comparing Nordmann fir and blue spruce as a Christmas tree. Nordmann firs impress with their soft, flexible needles and needle strength that lasts for weeks. Blue spruce trees have blue, fragrant needles that fall off after a week. As a Christmas tree, a 2 meter high Nordmann fir costs around 70 euros and the blue spruce 'Glauca' costs around 35 euros.
Care for blue spruce
The blue spruce is very easy to care for. In the bed, the conifer makes do with the natural rainfall. If you have planted the Norway spruce in a pot, keep the substrate slightly moist. The sunnier the location, the more often watering is required. Make the delicate time of having a Christmas tree indoors appealing to your blue spruce by spraying the needles several times a week.
The following lines explain how to properly fertilize conifers and multiply them successfully. What to do if the blue spruce needles can be found in comprehensible, compact tips.
Gloves are mandatory
The blue spruce is as beautiful as it is scratchy. With sharp, square, hard needles, the Norway spruce lives up to its name and leaves behind painful skin injuries. Please wear thorn-proof gloves when carrying out all planting and care work.
Fertilize
In the bed, fertilize a spruce tree in March with leaf compost or compost soil. Sprinkle the organic fertilizer on the root disc, rake the material in carefully and water again. Blue spruces in pots receive liquid conifer fertilizer in March and June.
Propagate
Propagation is quick and easy with cuttings, more precisely with cracklings. In early spring, tear off one or more annual, unwoody shoot tips. The side shoots in the lower half of the cuttings are removed. Place two thirds of a crackling, including the bark tongue, in coconut soil or growing substrate. The first roots form in the bright, warm location over the course of the summer. Spray the cuttings regularly with rainwater and keep the soil constantly slightly moist.
Blue spruce needs – why? – What to do?
Diseases, pests and location problems can cause problems for a blue spruce. The following table provides an overview of common causes and other symptoms with practical tips for countermeasures:
| Cause | Scientific name | Symptoms before needle drop | What to do? |
|---|---|---|---|
| Spruce needle rust | Chrysomyxa | yellowish-orange-brown spots on the needles, witch's broom | Check pH value, mulch, pour nettle manure |
| bark beetle | Scolytinae | Holes in the bark, piles of drill dust, resin flow | Cutting down trees, preventing bark beetles |
| Sitka spruce louse | Elatobium abietinum | yellowish-brown needles | Encourage ladybugs, spray potassium soap solution |
Popular varieties
- Glauca: most popular blue spruce as a Christmas tree, needles blue-green, light brown cones, height 10 m to 20 m.
- Blue Mountain: monumental spruce with a height of 15 m to 20 m, blue-green, pointed needles.
- Fat Albert: shines with light blue needles, pyramidal crown and a height of up to 12 m.
- Edith's Blue Spruce: garden-suitable variety with a height of 5 m to 6 m and growth of 15 cm to 30 cm per year.
- Nimetz: Dwarf spruce with a height of 80 cm to 100 cm, steel blue needles when sprouting creamy white.
- Fat Mac: cute mini blue spruce with a height of 50 cm, blue-green needles and a spherical growth habit.
FAQ
What is the difference between blue fir and blue spruce?
There is no difference. The blue spruce is often colloquially referred to as the blue fir due to its blue-green to steel-blue, square needles and an even, conical crown. In fact, they are evergreen conifers of the spruce genus (Picea).
Is blue spruce poisonous to cats?
No, the blue spruce is not poisonous to cats. However, the hard, sharp needles are indigestible for small cats' stomachs. If a blue spruce uses needles as a Christmas tree, first sweep up all the fallen needles before your darling is allowed to enter the room on velvet paws.
Red Spruce vs. Blue Spruce – What are the differences?
The Norway spruce (Picea abies) is the largest tree in Europe, next to the silver fir (Abies alba), with a growth height of up to 60 meters. The sharp, evergreen needles are 1 to 2 cm long, the cones reach a length of 10 to 15 cm. In contrast, a blue spruce grows to a height of 10 to 35 meters and has an evergreen foliage of 2 to 3 cm long blue needles. Their woody, brown cones are 6 to 11 cm long.
Is the blue spruce an allergy tree?
Every year, allergy sufferers report the torment of a Christmas tree allergy. In fact, blue spruce, Nordmann fir, and other indoor conifers can produce harmful molds. Their spores cause headaches, eye irritation, coughing and chronic nasal congestion in allergy sufferers.
Can you cut down a blue spruce on private property?
Felling down trees on private property is subject to various requirements in Germany. In principle, tree felling is permitted between October 1st and February 28th, provided that the wood does not serve as a winter quarters for wild animals. If these requirements are met, you are allowed to fell coniferous trees with a trunk diameter of up to 100 cm on your private property in accordance with the tree protection regulations.
Which is the most popular Christmas tree: blue spruce or Nordmann fir?
The sales figures in Germany speak for themselves. With a market share of a whopping 70 percent, the Nordmann fir is the most popular Christmas tree. The decisive criteria are soft, dark green needles and a long shelf life. When a Nordmann fir loses its first needles, the prickly blue spruce has already been standing in the living room without its needles.
