Conifers – Overall Height

Most conifers are graded to heights appropriate for their age and development.  The overall height grades are different for the four root conditions in which conifers are supplied:

Transplants

Many conifers do not transplant well as bare root plants if older than 3 years.  Plants older than 3 years should be supplied root balled or container grown.   For seedling and transplant conifers (e.g. Pinus sylvestris, Pinus nigra, Picea abies, Picea sitchensis, Tsuga heterophyll) up to three years old, the following overall height grades apply:

Height in cm Form
10-15 Seedling, transplant
15-20 Seedling, transplant
20-25 Seedling, transplant
25-30 Undercut seedling/Transplant
30-40 Undercut seedling/Transplant
40-50 Transplant
50-60 Transplant
60-80 Transplant

Cell-grown

Height in cm Form
10-20 Seedling
15-30 Seedling
20-40 Seedling
40-60 Seedling

Rootballed

The tables below show the height or spread grades for rootballed conifers in the following forms:

  • Dwarf/Bushy forms – e.g. Chamaecyparis obtusa ‘Nana Gracilis’, Juniperus squamata ‘Blue Star’, Picea glauca ‘Alberta Globe’, Pinus mugo pumilio.
  • Upright-growing; Medium Growth – e.g. Chamaecyparis lawsoniana ‘Ellwoodii’, Pinus mugo, Thuja occidentalis ‘Rheingold’, Taxus baccata ‘Fastigiata’.
  • Upright-growing: Vigorous Growth –  e.g. Cedrus libani, Chamaecyparis lawsoniana, x Cupressocyparis leylandii, Thuja plicata + cvs.

The tag colour indicates the internationally accepted marking system for the height/spread grades.

Dwarf/Bushy Forms

Height in cm Tag Colour
12-15 not applicable
15-20 Blue
20-25 yellow
25-30 Red
30-40 White
40-50 Blue
50-60 yellow
60-70 Red
70-80 White
80-90 Yellow
90-100 Blue
100-125 White
125-150 Blue
150-175 Red
175-200 Yellow
above 200 in 50 cm. steps.

Upright-growing; Medium Growth

Height in cm Tag Colour
30-40 White
40-50 Blue
50-60 Yellow
60-70 Red
70-80 White
80-90 Yellow
90-100 Blue
100-125 White
125-150 Blue
150-175 Red
175-200 Yellow
200-225 Blue
225-250 White
250-275 Yellow
275-300 Red

Upright-growing: Vigorous Growth

Height in cm Tag Colour
40-60 Blue
50-60 Yellow
60-80 Red
80-100 Yellow
100-125 White
125-150 Blue
150-175 Red
175-200 Yellow
200-250 Blue
250-300 Yellow
300-350 Blue
350-400 White

For Specimen Conifers, the overall height AND spread is specified.   For species and cultivars with a vigorous growing top leading shoot, half of the annual top shoot is the upper limit for the measure of the height e.g. Pseudotsuga spp, Picea omorika.

Container-grown

Dwarf and prostrate conifers such as Chamaecyparis spp., Juniperus spp., Picea spp. and Tsuga spp. can be specified in 15-20 cm, 20-30 cm and 30-40 cm containers.

The medium and vigorous growing conifers such as Abies spp., Cedrus spp., Chamaecyparis spp., x Cupressocyparis spp. and Juniperus spp. can be specified in 20-30cm, 40-50cm, 50-60 cm and 60-70 cm containers.