The Planting Season – When Is It

and Why is it?

Many people will come to a point in their lives when, for whatever reason they want to plant something. And as modern lives and trends take us further away from the more ‘natural’ lives that people lived even only a few decades ago, our need to know about when is the right time to plant trees, shrubs, bulbs, bedding plants etc., etc. becomes more important. The key reason for this is really to do with increasing the survival rate of the plant that we want to plant. Kind of obvious I suppose.

It has always been said that the planting season refers to the winter period from November to March, and this is to do with ‘dormancy’. However, dormancy is not necessarily at the same time of year for all plants. Added to which, the need for a plant to be dormant in order to plant it with a good chance of it surviving can be totally removed if certain steps are taken.

Dormancy generally speaking, is when the period of flower production and therefore seed production and overall growth comes to an end. This period generally ends because of the tilt of the Earth, and the shortening of daylight hours and the resulting reduction of average temperatures. Once these changes start to take hold, then ideal conditions for plant growth etc. declines and a state of dormancy takes over.

In the case of many trees and shrubs, their leaves are shed and the high levels of transpiration significantly reduce. In the case of Herbaceous Perennials, their top growth dies right back to ground level, and for Annual Plants, they die off completely. 

So it is as a consequence of the dormancy that the changing of the Seasons creates that it then becomes very much more safe to lift and move particularly deciduous plants without much loss of moisture.

Conifers and evergreen plants on the other hand still have their leaves after the season changes. They are however, still affected and as a result their transpiration rate does reduce. A problem can occur with such plants in the dark depths of winter if conifers are not container grown and are lifted from an open ground position, severing and losing much of the fibrous root in the process. It may seem surprising to the layman that they can then die from drought stress because, having foliage as they do, transpiration still takes place and a dry winter wind can draw the moisture from them at a time when they have no means of taking up water because much of their fibrous root is now gone.

It is for that reason that we would always suggest that you only transplant Conifers at a time when they are actively growing, probably no sooner than April and no later than late September.

However, in situations where a much loved or important evergreen plant must be moved, there is a way to help increase its chances of survival. The application by spraying of a product call an ‘anti-transpirent’ helps to reduce the rate at which the plant loses moisture through its leaves, and thus helps in the process or re-establishment, particularly of the root system. 

You may have come across this product at Christmas time, as it is an anti-transpirent that can be sprayed on the foliage of Christmas trees to help prevent needle loss indoors.