Propagation time in John’s summer garden

John is sharing his experience and some of his plant cuttings this week

Keen gardeners have always welcomed admiration for their horticultural success and are only too happy to let someone have a cutting, spare plant or a bit of a plant that has layered itself.

In my earlier apprenticeship days, propagation in all its forms was a major part of our training and we gathered a lot of plants for our garden as our wee cuttings grew into bigger plants. Our older experienced journeymen would always bring us some cuttings to test our skills.

Today it is now us older gardeners that help others with cuttings, spare plants and wee bits with a few roots showing.

Garden plants have had a great boost to growth this year with very favourable weather, at least so far.

Although propagation goes on all year round, there are many plants we can grow from summer cuttings as growth matures but is still active.

Lamium White Nancy is an attractive silver ground-hugging plant with shoots that root easily as they hug the soil.

Take some of these shoots with a few roots and pot up as they quickly establish as young plants.

Houttuynia is also propagated by lifting young shoots with roots on. Border phlox is also propagated from ground-hugging branches that root into the soil as they spread.

Bearded iris have now finished flowering and any clumps three years old will benefit from digging up, splitting the crowns and replanting into fresh soil.

The border pinks may still be flowering, but come easily from cuttings

Although propagation goes on all year, there are many plants we can grow from summer cuttings as growth matures but is still active

of non-flowering shoots about three to four inches long and potted up with potting compost with added grit for extra drainage.

Many dwarf evergreen azaleas, rhododendrons and camellias can be propagated both by layering as well as cuttings, but for success you will need to use ericaceous compost with added grit, sand or perlite.

Take cuttings from shoots that still look like they have not finished growing.

Size again about three to four inches long. Remove most of the leaves except a couple near the top and if these are large, cut half of the leaf off.

Water in well and keep in a sheltered, light place away from direct sunlight. Most of these cuttings will root better with some hormone rooting powder.

The dwarf Japanese azaleas can also be layered. Take a low shoot near the ground and scrape a wee bit of bark off then lower it into the soil while still attached to the parent plant.

You will need a peg to keep it in the ground and cover it with soil.

It may be at least six months before it is rooted sufficiently to be cut off and either potted up or transplanted to another spot to grow on.

Heathers will come from cuttings two to three inches long placed in ericaceous compost with added grit, but keep them away from direct sunlight.

Remove growth from the bottom one or two inches and take the tip out to encourage it to branch once it roots.

Other plants that root well from mid to late summer as semi-ripe cuttings include lavender, cistus, rosemary, fuchsia, senecio, hydrangea, euonymus, Lonicera Baggesen’s Gold and many others.

My two favourite very colourful succulents, the ice plant, Delosperma cooperi and D. nubigenum are easily propagated from short shoots a couple of inches long put direct into the soil.

They always root and grow very quickly but like very well drained soil in a sunny position.

Perfect at the top of a south-facing wall where they can hang down happily and soon burst into flower.

Pictures: John Stoa. Clockwise from main picture: Delosperma cooperi 2020; Hydrangea Charme cutting; Pink cuttings now rooted; and Lamium White Nancy.