Eucalyptus camaldulensis - progression

[Matt S]

River Red Gums are my favourite tree and I've been enjoying the number of examples that have popped up recently on ausbonsai, so I thought I should capture the progress on one of my starters before it gets too advanced.

This tree was grown from seed collected about 12 months ago from a huge tree in a local park that dropped a massive branch. My daughter and I scoured the branch (that was as thick as my waist) and found a few seed capsules that were ready to go. A handful of seedlings resulted and I kept only 2 of the strongest.

The seedling was transferred to the current black pot and left to grow, and I chopped all the major branches (bar one) about 3 weeks ago.

20200109 redgum progression a.jpg

20200109 redgum progression b.jpg

20200109 redgum progression front.jpg

Not much to see so far but the intention is for a tall slender, asymmetrical tree, something like this hastily-drawn-and-photographed-in-bad-light-sketch:

20200109 redgum progression optimistic goal.jpg

Matt.

[Matt S]

Lots of growth on this tree and I'm thinking I may have to find a larger training pot. It currently sits in a shallow tray of water and gets a handful of fertiliser every few weeks.

Not much to show other than the trunk is thickening and I left the topmost shoot grow too strong so I had to cut it back hard. The lowest branch is a sacrifice to thicken the base and so the next highest on the left is supposed to be almost as thick as the main trunk, so it will have to be left alone for a while to catch up. I'm trying to not let any area grow too strongly at the expense of anywhere else, which is why I'm often cutting it back even at this (very) early stage. It's a strange way to build a tree but hopefully it will work out.

20200424 redgum progression before trim.jpg

20200424 redgum progression after trim.JPG

Matt.

[MJL]

Hey Matt,
I hope you're well and managing through physical distancing.

I am really enjoying my River Gums - essentially inspired last year's native conference in Melbourne, the [Natural] comp on this forum and your (and others) enthusiasm too. They are certainly vigorous and responsive if a tad uncontrollable....

A couple of observations and some related questions:

The river gums at my joint are still growing ridiculously fast - I took a photo today (again) but I won't pollute your thread with it. Do these guys ever stop growing?

The regime of breaking branches and intermittently pinching the new growth tips is helping to ramify the tops of the trees. To me - the control of vigour feel quite logical .... and I think the leaves are getting smaller. (I really like what happens when breaking (as opposed cutting branches) even on young branches the end sort of frays and looks really quite good - natural, I think. Do you ever hands snap/break gum branches rather than cut?

The response to breaking is both as expected and a tad random. What I mean by that is sometimes the growth occurs where expected - much like you'd expect when cut 'n' growing say an elm but sometimes the response is quite random with growth occurring the oddest/unexpected spots. Does this happen to you too or through your experience, have you managed to fully understand the way they respond and perhaps cut differently?

I also note that you are keeping a sacrifice branch which makes sense for your design. I am a bit torn, I see numerous river gums with big low branches almost multi-trunk style but not really ... anyway, I have noticed that whatever I am doing to my young tress is causing them to sprout from the base - a lot ... (Not suckers - just low down on the main trunk.) I quite like this - I have the option to keep a branch or branches, for that low-down multi-trunk style or keep for a little while to help fatten and then cut away.... I am guessing this low growth may be some for of stress response to my constant breaking or just the sheer volume of water they are sucking up with the pot 1/2 submerged. Do these low branches occur for you and are they an option to thicken trunks as opposed to the 'traditonal' sacrifice branch.

Interested in your thoughts.

Cheers,

Mark

[Matt S]

Hi Mark,

Thanks for your post, lots to talk about.

Do these guys ever stop growing?

Ha. Not very often. Mine slow down mid winter and mid summer, but the young vigorous ones keep growing as long as there's water. I guess that's one of the reasons they grow so well in dry creek beds that flood occasionally, they have to respond quickly to the presence of water and get their growth on while conditions are good. My most mature tree is nowhere near as vigorous, it grows fastest over Spring and Autumn but is quite sedate at other times. Thank goodness.

Do you ever hands snap/break gum branches rather than cut?

Sometimes, mostly on the underside of branches where there is often deadwood. Other times I like that smooth sinuous transition to smaller branches.

sometimes the response is quite random with growth occurring the oddest/unexpected spots.

I notice this too, and I haven't been able to predict what will happen based on the type of cut. Sometimes I cut back hard and leave a long stub hoping that shoots will appear somewhere along the stub (where I know there were internodes previously), but it doesn't always happen. Sometimes I get shoots on the stub, sometimes at the base of the stub, often at both. Cutting a single branch without pruning the rest of the tree can sometimes result in very few shoots forming and they tend to be weak, unless the branch is high on the tree. Pruning hard on the entire tree will result in shoots coming out everywhere.
Strong shoots at the base of a branch will sap the energy from a branch quickly, likewise a strong upward shoot along a branch can cause the rest of the branch to die off, so keeping the growth balanced is important and sacrifice branches can't be left to grow rampant. A few times I've tried to thicken up a branch by letting it go and continuing to tip prune the rest of the tree, and I've lost the rest of the trunk.

I have noticed that whatever I am doing to my young tress is causing them to sprout from the base - a lot

I've had that too, usually after a hard prune or the tree has gotten stressed. Once again I''d be wary of letting them grow more vigorously than the main trunk unless you intend to keep them for that low branching form you described. I guess you need to decide early on the form you want and then stick to it. For the tree in this thread, the lower branch won't be allowed to get too vigorous. If it approached half the thickness of the main trunk then I'd put a stop to it. Once the tree decides to allow a branch to lose vigour in preference to another, there's bugger all you can do about it.

The other thing I've noticed is that when it's time to reduce the size of the leaves and get some ramification, the tree will initially respond with more vigorous growth and you have to keep fighting it over and over until eventually the whole tree gives in and starts producing smaller leaves, with the occasional shoot that makes a break for it. Never a dull moment.

Thanks for the questions and keep posting your observations, I'm following your trees with interest.

Cheers,
Matt.

[MJL]

Thanks for the detailed response Matt. Great that we can learn and watch from a distance like this.

On a completely separate note - I awoke to the neighbour playing The Last Post on his bagpipes in his driveway this morning. A thoughtful tribute. Lest We Forget.

[Matt S]

Since this is supposed to be a progression thread I'd better post a progression. This Gum was transferred to an orchid pot in Jan 21 and it stands in a tray of water over summer. I let the branches grow as they like, then roughly every 6 months I cut back any over vigorous branches and wire anything I think that needs it. This regime slows down the thickening but it lets me have more control over the relative dimensions of the branches to each other. Here is a before and after photo of the most recent pruning. As usual the top branches are cut hard and the lower ones are left alone.

20220208 redgum progression a.jpg

20220208 redgum progression b.jpg

Looking at the older photos I can see that the framework is thickening up nicely and you can see the original plan starting to develop.


Matt.

[Joshua]

Great thread so far, I hope you keep it up.

If you don't mind me asking a few details:

• What are the (rough) dimensions of the trees so far and the pots they're in?

• What kind of substrate are they in? What's your mix?

Regarding the tray of water over summer,

• Do you water as normal and let them sit in what runs out or do you just top up the tray for a kind of bottom-watering?

• How deep is the water they sit in?

• Does this not encourage mosquitoes?

I have some red gums I started from seed a year ago, about 7. For now they're mostly in quite large and deep pots with normal potting soil. Planning to reduce to just a couple of the best ones to make space, also smaller pots.

[Matt S]

Hi Joshua,

After the trim the tree is about 1m high, sitting in a 30cm pot.

The mix is about 50% premium potting mix and 50% inorganic material, typically a mix of pumice, zeolite or whatever I have around at that time. When it's time to work on the ramification I'll move to a more inorganic mix, usually 1 third organic to 2 thirds inorganic.

I water from the top and the tray just catches the runoff. As I fertilise using organic pellets scattered on the surface I figure the water needs to come from above.

The tray is only a few cm deep and is usually empty by the end of each day, so mozzies aren't a problem.

Hope that helps!

Matt.