When we think of great times of the year for bonsai, it’s not likely that the month of August comes to mind. No surprise, right? August is (often dangerously) hot. Even if you do some collecting in August, you generally feel like you need a head examination afterwards. No matter what work you do on your trees, you know that growth for the remainder of the season is going to be muted at best.

But don’t despair. There are bonsai activities you can do in August that not only make sense, they can actually move the development of your trees forward that extra step. Let’s look at a couple:


When we wire our trees in spring, the strong growth into summer usually makes new branches push hard against their wires and this begins the process of setting them in place. So we typically must unwire our trees by late spring, to avoid potential wire scars. As happens with most species, the new branches will continue to grow and slowly but surely point themselves upward. Apical dominance is natural, and one reason we wire trees is to overcome it.

Water-elm8-20-16-2Here’s a classic example. This water-elm, Planera aquatica, got its first round of wiring in spring when all the new young shoots were ready to be initially positioned. The last of that round of wiring was undone about three or four weeks ago. The tree has responded by sending a whole host of new growth pointing upward. This is not going to make for a good bonsai, so it’s time to reapply the wire. Not only will I get the benefit of re-establishing the design I have in mind, when fall approaches all of these branches will swell with stored food. As you might surmise, that means all of the wire I apply now is going to come off by the end of the growing season.






Here’s the tree about 15 minutes later. If you compare this photo with the first one, you can see the design has been re-established. The upward trend of the branches is no more. Now, this fight isn’t over yet. It’ll continue throughout the life of the tree as a bonsai, just in a different way. In time it’ll only be the smallest shoots that grow straight up.

If you don’t currently do any late-summer wiring, you may want to add the practice to your bonsai development techniques. A lot of design work can be accomplished at this time of year – the hard month of August.


Another problem that can arise during the growing season is accumulation of grime on the trunks of your trees. This is mostly due to our watering regimes, and in summer the added issue of lack of air circulation (for those of us in non-breezy locations). Mold can easily set in, in such circumstances.

Water-elm8-20-16-4In this closeup photo, you can see I’ve got a bit of mold buildup – this despite the fact that the tree has been in full sun all year. Time to pull out the vinegar-water mix. I use a 50:50 mixture of household white vinegar and water in a spray bottle. I spray this mixture on the areas of the trunk (and, if needed, branches) that need cleaning, then scrub with either an old toothbrush or stainless steel brush. For trees with fragile bark, it’s best to use only a soft-bristle toothbrush and scrub gently.



And here’s the after photo. Cleaning the trunks of your trees will bring out their beauty, plus it’s good for their health. The bark of trees is designed to allow for gas transport via tiny pores called lenticels. When mold or grime builds up, this gas transport is hampered and the tree comes under stress. So a periodic cleaning is advisable.








Now this water-elm is ready for the remainder of the growing season. The next thing I’ll do is remove the wire in fall – so other than the necessary watering, it’s back to benign neglect.

This is a superb water-elm specimen that will make a great statement in anyone’s collection. It’s available at our Elm Bonsai page, and ships now.