a perennial favorite and summer wonder

If you’ve been on a summer walk in recent weeks, you’ve probably seen a red gum tree blooming, Corymbia ficifolia.

This species comes from a compact area southwestern Western Australia but it has been a firm favorite with Australian gardeners for over a century. It is often planted in home gardens, streets and parks, which shows its versatility and attractiveness.

But while its huge, glowing flowers attracted the attention of gardeners early on, this summer plant’s path to becoming a successful urban tree wasn’t always effortless.

Difficulty growing from seedlings

The red flowering gum is a compact to medium-sized tree that can reach a height of about 15 meters, but most trees are ten meters or less.

Its leaves resemble a fig, as the name suggests, ficifoliasuggests. They are shorter, wider and greener than many eucalyptus leaves.

Although it may be sensitive to frost when teenage, it usually does well once it reaches a height of two or three meters.

Red flowering gum tolerates a wide range of different soil types, and its often massive lignotubers mean it copes well with occasional fire. (Linotubera is a swelling at the base of the trunk containing dormant buds and carbohydrates).

Corymbia ficifolia can produce flowers in white, pink, orange or red, but red is the favorite.

In fact, over many decades, great effort has been put into obtaining commercial samples that reliably produce the desired color.

This can be easily achieved with other plant species. However, eucalyptus trees are extremely challenging (but not impossible) to grow from seedlings and to graft.

Most red gums are grown from cuttings, where there is always a risk of variation in characteristics, including color. The seedlings are clones and therefore have the same color as the single-parent tree. In turn, seedlings have common genetic material from two parents, which leads to variability in color.

Much of our knowledge about eucalyptus comes from forestry, which enjoys enormous commercial interest and research funding.

However, great potential Corymbia ficifolia as a popular nursery product, it has generated continued interest, effort and expense from gardeners for decades.

History of gardening

All sorts of experiments have been carried out to propagate red flowering gum seedlings and represent milestones in our knowledge and research on eucalyptus trees.

Already at the very beginning, at the end of the 19th century. classic selection techniques were used to obtain seeds from the best red flowering gums. The idea was that while not all would produce brilliantly colored offspring, many would Good color due to its excellent origin.

Nursery production was in full swing at the end of the 19th century, so attempts were made to grow it Corymbia ficifolia from cuttings was inevitable, but it happened little if any success.

However, already in the 1950s, foresters knew that it was material from juvenile eucalyptus more likely to be successful.

Some have tried to grow seedlings using teenage seedling material or the shoot tops of trees known as glowing red.

Others tried to propagate from epicormic shoots (growing just under the bark) and lignotuberous shoots, which have many youthful features.

Although it had some successes, the pace was far too sluggish to be commercially viable. Growing flowering red gums from cuttings was still the way to go.

In the 1970s it began to be used root hormones allowed for greater success.

But soon tissue culturewhich involved the utilize of sophisticated mixtures of hormones in sophisticated growing media, proved to be an effective propagation technique.

This he workedbut cultivating eucalyptus tissues was not effortless; Many costly trials and errors had to be endured before success was achieved.

The lack of consistent success means this form of reproduction has yet to be taken by industry.

While all this was happening, other people in research labs and nurseries were also trying to graft selected red flowering gum shoots established seedling rootstocks.

Previous seedling work and contemporary tissue culture work have provided some insight into what may be required to successfully graft a flowering red gum onto the rootstock of another eucalyptus, or even its own species.

But it took time and effort before real success occurred achieved at the turn of this century.

Grafting often results in smaller trees that flower prematurely and profusely, which is probably why they are smaller. Early and copious flowering consumes a lot of the tree’s resources, so it often becomes smaller.

Demanding work and good study

Nowadays we can embrace variations Corymbia ficifolia taken for granted. We may see a mini red or little orange, a lofty pale pink fairy, a summer red, an apricot dawn or a white snowflake in spectacular garden or street plantings.

If you see a very compact or very huge flowering gum with glowing colors, there is a good chance it is one of the newer grafted varieties Corymbia ficifolia.

If you have a grafted variety in your garden, be sure to remove any shoots that may grow from under the graft. They can grow very quickly and return to the original form and color of red flowering gum.

I still have a supple spot for the spectacular, larger, red flowering gums. Perhaps it comes from childhood memories, or recalling when, in the mid-1980s, my students and I tried (with mixed success) to grow red-flowering gum seedlings using various combinations of plant hormones.

Or maybe it’s because we still haven’t learned all the secrets to producing great specimens every time.

But most likely it’s because I know how much demanding work and good science went into making it great Corymbia ficifolia the specimens we see today.