Growing Methods

Committed to growing strong, true to type advanced trees, with solid calipers and developed branching, Ronneby Trees uses a number of cultural techniques to produce the best possible established plants.  These include:

  1. Root Development
  2. Formative Pruning
  3. Growing Medium

1.    Root Development

Even though out of sight, roots need to be managed carefully.  A good root system is the key to strong, healthy, vigorous growth over the entire life of a tree. By using our internationally patented growing containers we can supply trees with an outwardly pointing, fiberous root system, ready to re-establish immediately.  This gives a big head start over plants grown in conventional pots.

SpringRing® Air Pruning Container

In response to increasing demand for trees able to be successfully planted throughout the year, Ronneby Trees developed the reusable SpringRing® container. SpringRing® utilizes the principles of air root pruning to produce a healthy tree without the traditional fault of spiraling.
Roots naturally grow outwards, searching for water and nutrients.

In a conventional nursery container, roots reach the edge of the pot, are deflected, and continually spiral the outer edge of the pot.  This necessitates trimming and pruning of the roots when transplanted into the landscape, leading to root disturbance and transplant shock, and potentially tree failure.

In a SpringRing® container however, roots are directed into outwardly pointed open ended cusps, preventing spiraling and air pruning the tip of the root.  The response of the plant to the air pruning is to send out more roots to compensate for the loss, leading to the build up of a dense, fiberous, outwardly pointing root system.

This increase in fiberous root benefits an advanced tree in a number of ways.


  • - Water and nutrient uptake is enhanced due to the increased root volume.
  • - The tree is better able to establish once transplanted as it has a larger root mass.
  • - No teasing or cutting of root material is required when transplanting, reducing shock and enabling year round planting.
  • - The continual root growth and branching leads to stimulated and strengthened top growth in the areas of caliper development and branching


Trees also respond better to being grown in this way as SpringRing® containers have excellent drainage promoting aerobic activity and eliminating root rot.

Root Control Bags


It has long been accepted that the best way to grow an advanced tree is to replicate the conditions into which the tree will ultimately be planted.  The widely accepted standard utilized to achieve this replication has been to grow trees directly in the ground until they are ready for relocation.  To remove the trees from the ground required the grower to sever the trees roots with a spade damaging roots vital to the future success of the tree. The result of such root damage became evident when the tree was planted at its final destination.  The severed roots retarded establishment and inhibited the growth of the tree.  Trees grown in accordance with this method are referred to as balled and burlapped trees.

Trees grown in a Root Control Bag ("RCB") enjoy the same benefits as trees grown directly in the ground without the disadvantage of having their root systems severed and wounded upon harvest.

The young tree is planted in the ground with the RCB enclosing the fledgling root system.  As the roots grow, fine feeder roots are able to penetrate tiny holes in the felt-like fabric wall, without spiraling, and grow out into the surrounding soil.  Here they are able to continue to provide water and nutrients back to the plant via the xylem (water and nutrient conducting tissue).

However, the normal thick, carbohydrate rich outward growth of the roots via the phloem (tissue conducting plant manufactured sugars and carbohydrates around the plant) is restricted to within the confines of the RCB, minimizing the loss of carbohydrates that would normally be used in the outer roots.

This results in a rootball that has the main structure of the root system contained within the diameter of the RCB, and can therefore be harvested without the wounding or severing associated with more traditional techniques.

An added benefit of this method of production are the carbohydrate rich nodules that form at the point of root restriction within the bag.  When the tree is harvested and fine feeder roots are removed for transport, these nodules act as a rich source of energy for the newly transplanted tree to re- establish from.

Due to the fact that there is some root disturbance, trees grown in this way are principally available during late autumn, winter and early spring, when tree growth is slow or dormant.

2. Formative Pruning

It takes many years to produce an advanced tree.  Right from the very beginning any plant to be grown on requires specialist treatment.  Formative pruning is undertaken at regular intervals to ensure correct form, strong branching, heavy caliper, regulated growth and uniformity.


By pruning in this way, encouraging branching and caliper development, we are able to eliminate over staking.


If a tree is allowed to grow too quickly, the resulting growth will be soft and sappy.  Therefore many nurseries will "overstake" by putting a stake hard up against the trunk. This results in a tree with a soft trunk, or caliper, that potentially struggles to support its own head weight when planted out and the stake is eventually removed.

In combination with our patented containers, we are able to supply trees that are strong, healthy, fully hardened and ready for transplant.

3. Growing Medium

Over many years of production and trials we have developed our own growing medium for the production of above ground, SpringRing® containerized trees.

By manipulating both the physical properties of our growing medium and the nutrient content, we have been able to enhance the benefits of the SpringRing® growing system, aiding in the development of healthy well formed trees.

All organic matter included in the medium is fully composted and then mixed with other ingredients on site, giving us maximum flexibility to match individual tree species requirements.