How to promote shrubby growth in Amelanchier Alnifolia

(Question)

Dear Master Gardener
I recently had a Amelanchier Alnifolia planted in my garden that our tree maintenance people bought from Dutch Nurseries. I wanted this particular serviceberry because I want to achieve a kind of “grove like” look and I understand it has multiple suckers. The tree they planted is the species I asked for but it has just the single stem at the moment — it is quite tall (about 10 feet) and I am wondering if it can still put out offshoots at the base to promote many stems — and if there is anything I need to do to assist it. Many thanks for your help!

(Answer)

Thank you for your question for Toronto Master Gardeners about your Amelanchier alnifolia. This plant, known by a variety of common names including saskatoon (derived from the Cree word “Mis-sask-quah-too-mina”)(Usask) and serviceberry, was an important source of saskatoon berries for the Indigenous peoples of the prairies and western Canada. They were so plentiful in the prairies that the city of Saskatoon was named after this tree/shrub.

Yes, your Amelanchier alnifolia can be pruned to induce its natural production of offshoots. Without the cultivar name (there are approximately 8 varieties), it is difficult to determine how plentiful the production of shoots will be. Perhaps the nursery may be able to provide the cultivar name. The depth at which your tree has been planted is important for shoot production so you will need to pull the mulch aside to determine this. Too much depth can inhibit the development of basal shoots.

With either gradual annual pruning or removal of the single stem, you can develop the bush form of your plant. Since your tree was recently planted, a gradual reduction in size through annual pruning of a quarter of the top growth may be preferred over removal of the single stem close to the ground.

Refer to pages 45 to 59 and Table 5 pages 57 to 59 of the following publication for details:

Kaulbars, C. (2013). Saskatoon berry production manual at the following link – https://www1.agric.gov.ab.ca/$Department/deptdocs.nsf/all/agdex14362/$FILE/238_20-2.pdf

Some key points:

  • Prune only when fully dormant in late fall as this is less stress for the plant
  • Use sharp appropriately sized bypass pruners to prevent bruising
  • Sterilize pruners with each cut.
  • Apply water and fertilizer in spring
  • Regularly check your plant for insects and diseases such as powdery mildew so that these may be treated early

All the best with caring for your Amelanchier alnifolia.