Nov 5, 20215 min read

Greenbourne Nursery about Propagating in Spring

Updated: Jun 16, 2022

✦ Creating plants is one of the true joys in horticulture.

The raw excitement of Spring has begun to ease off and we all now attend to our recently acquired plants, obtained in a dizzy state of euphoria that the onset of the growing season always brings.

We now reassess our gardening priorities from a frenzied bout of planting into a rhythmic balance of feeding, weeding and watering. While watching the garden is precisely why we garden, it seems us gardener types always like to be doing something more with our vegetative buddies… so we propagate.

Creating plants is one of the true joys in horticulture. There are many techniques and methods that we have access to.

Seed

The simplest method of plant propagation. Always an exciting journey to see the emergence of a small plant as it arrives out of its sleeping cocoon.

I have found memories of a great gardener once talking to me about a seed. He would remark how IBM (the computer company) would claim to have developed the first micro-processor… this is the first one he would say as he held a tiny seed in his gnarled, well-aged fingers. And how could you argue with him, within that tiny seed casing was all the information that was required to create something absolutely amazing.

There are great seed raising soils at the nurseries these days. They are nice and fine in particle size and have ingredients that retain the optimum moisture levels. There are also specific germinating kits that contain peat plugs that allow you germinate seed individually within a mini-igloo environment. When germinating seed like this you can minimise transplantation shock as the roots have little disturbance.

There are two terms that you may come across when you read literature on seed germination. Scarification and stratification, these are pre-treating methods. Scarification involves breaking down the hard seed coating that some varieties have. This can be done physically by rubbing seed on sanding paper or shaking around in a container with small stones in it. Hot water is an effective method for some types as it aids in cracking and softening the seed coating. Stratification is a method where we are attempting to mimic a seed's natural environment. Storing some seed types in the refrigerator creates an artificial winter which helps the seed to break its dormancy.

A final tip when germinating seeds, particularly in containers, is to cover them. There are many critters that will feed on both the ungerminated seed and the newly emerging seedling. So, cover with wire or a clear container to give them the best possible chance.

Plant cuttings

When taking cuttings from plants to propagate with, always have clean, sharp, sterilised secateurs - this will minimise any chance of infection and enable a nice untorn cut. The use of a rooting hormone will greatly increase your success rate too. Rooting hormones contain natural and synthetic auxins which encourage roots to form. They come in either a powder or gel. Simply apply them to the southern end of the cutting prior to inserting it into the propagating mix. Again, your local nurseries have great propagating mixes which are well designed to give your cuttings the best chance. Once your cuttings have been inserted into the propagating mix it is best to store them away from direct sunlight in a moist, humid environment, ideally an igloo like situation. Keep the cuttings well misted with water during the first few days.

Plant cuttings are basically classed into 3 distinct categories: Tip (softwood), semi-hardwood and hard wood.

Tip (softwood) cuttings

A cutting made from the current season’s immature growth. Take cuttings about 5-10cm long, cutting just above a node. The cuttings are liable to wilt if not dealt with immediately, best done in the early morning. Great species to try are Coleus, Aster, Chrysanthemums and Fuchsia.

Propagating in Spring, Greenbourne Nursery, featured on Brilliant-Online — Chrysanthemums

Semi-hardwood cuttings

A cutting made from the current season’s growth just as it begins to harden at the base. Take cuttings about 10-15cm long. They are firm to touch at their base but still active in growth. Great species to try are Callistemon, Azalea, Camelia and Daphne.

Hardwood cuttings

A cutting made from the fully ripened tissue of a woody plant. They are firm to touch all the way through the length of the cutting. Take cuttings 10-20cm long. Great species to try are Rosa, Viburnum, Prunus and Morus.

While seed and cutting are the most popular methods for home gardeners to use, nature has been kind enough to offer us an abundance of ways to reproduce certain varieties. Here is a quick summary of a few methods of note.

Division

A super economic way to reproduce plants. Really effective with a lot of clumping plants such as the ornamental grasses. Simply dig up the clumping plant (or remove it from the pot) and begin to ‘tease out’ the root ball. By removing the soil from the roots, the separate plants will begin to come away from the main clump, simply giving each individual plant a minor root prune and pot separately.

Rhizomes/bulbs/corms/tubers

Many plants store energy and their genetic imprint beneath the soil in modified root systems which fall into various categories. These can be dug up and used to produce more plants. Rhizomes and corms can be cut up into sections and replanted to form new plants, whereas bulbs and tubers can be separated from each other and divided up into individual pieces to create a host of new plants.

Layering

This process can be done two ways: ground layering and air layering. Ground layering involves pining an attached limb of the plant to the ground and submerging a nodal piece beneath the soil. When done with appropriate species the plant will produce a root system from the node. From here the piece can be removed from the parent plant and potted up with its new root system. Air layering works without pinning a piece to the ground but bringing the soil media to the limb. A clump of peat is best used, it is moistened and then wrapped around a nodal point on a plants’ limb. The peat is then held in place with a moist bit of cloth or in some cases foil. Foil works really well as you are able to mould it around the peat ball and the limb. Over time a root system will begin to form within the contained peat ball. When the roots are sufficient enough in size the piece can be pruned from the plant and potted up with its new root system.

The plant kingdom really does provide us with year round entertainment. Propagation is just one of the many stimulating tasks we can perform in and around our garden. Please get out there and give a few of these techniques a go and share a few small gifts with family and friends. As I have mentioned before, the act of creation certainly gives you an amazing and satisfying feeling. Pop out to the nursery for any extra advice you might require or as always just for a friendly chat.