Tree Tips

February 2024

This year we’ve had a steady stream of soaking rain, but very little sticking as snow pack in the mountain watersheds which may create a problem later in the year. Still I hope there is more on the way in February and March. Water quality for our trees is better when there is an abundant source and the water company doesn’t have to pump from more compromised sources.

However, like last year, I totally got used to Mother Nature watering my trees. I need to get back into doing it myself. When we have a rainstorm the soil becomes completely saturated and doesn’t need to be watered every day. When it’s dry and we water with a hose, many times it does not get saturated and will need to be watered more often. When the akadama on the surface turns light brown at the surface, it's time to water. If there is too much rain, put a block under one side to tilt and drain the pot to insure you don’t drown your trees.

WEEDS! WEEDS!! WEEDS!!!

My yard looks like a yellow flowered oxalis field. And my bonsai pots have some too. Put a reminder on your cell phone to check for weeds and other needs every week.

Continue to transplant your trees. Do it now! Healthy deciduous trees that have a good base in which healthy radial roots occupy the inner core do not need to be bare-rooted. Just remove the exterior edges and long gangly roots and the circling mass on the bottom. Weak deciduous trees can be partially bare rooted, remove the field soil on 1/2 or 1/3 of the rootball, replace with fresh soil and leave the rest of the root ball intact. You can get the rest cleaned out when you transplant in a year or two. Conifers should not be totally bare rooted but at least one section of old field soil should be cleaned out if any still remains — just like in the weak deciduous trees above.

Grafting

Grafting time is here for pines, junipers and other species. Now and fall are perfect times to graft. Keep some shoots toward the side of the tree to use as scions. But don’t use the very tip of a vigorously growing shoot as this can be too strong a scion for the graft to take. Plan where you will be putting these grafts. If you will be grafting deciduous trees, cut some scions and put them in damp paper towels and in the crisper of your refrigerator. When the tree buds start moving, bring them out and use them for your grafts. Remember that you will have better success if the understock’s sap is moving before the scions do.

Tree Improvement Plan

Remember the project we talked about five or six years ago when we were to work on trees at different stages of refinement? Start on a couple trees now, develop last year’s starters and refine a couple of last years developed trees as well as the six you refined a number of years ago. When you get multiples of nicely refined trees, keep the best, and trade the extras for better and better trees. The key is to keep only the best of these for your own collection and really concentrate on them. Lose the rest. Don’t start working on another one until you have completed as much work as you can on one for this year.

Develop your techniques. Learn from what you did last year. Practice whenever you can and you will succeed. Practice on workshop nights. Practice at home. Practice in your sleep.

Dormant Spray

Remember to use dormant spray again around Valentine’s day. It is best to do it on a day that the temperature will not get above 55ºF or you could burn the foliage. Try copper spray or lime-sulfur, except on Ume, spruce, azaleas and tropical trees, to protect deciduous and fruiting and flowering species. This will head off big problems later on.

Pruning

When you cut back on branches this month, leave just a tiny stub for die back. If you cut an entire branch, do not cut into the branch collar, which is that swollen area where the branch attaches to the trunk. Remember that the tree is getting active and will soon generate new growth to heal over the cuts.

Now that the pine needles have matured and hardened, if you haven’t already removed them, it is time to take off most of the old needles and some of the newer needles on the plump and healthy shoots. This opens up the interior of the tree to the sun and airflow that is necessary to generate back budding. Remember to leave more needles on lower branches and interior buds, and if weak, don’t touch at all. Watch out for those that have already started new tiny buds. It would be a shame to accidentally pluck out those tiny buds you try so hard to generate.

Collecting Trees

Plan to collect some trees this year. Whether it is a neighbor's pyracantha hedge or an oak dig or a trip to the mountains or desert for junipers, don’t pass up this great way to find super material. It also gives you a chance to observe the branching and twigging patterns of your favorite trees as they grow in nature. Collect interesting mosses and lichen in flats for use at show time. The best accent plants for a bonsai are those that are growing alongside the tree in the wild. 🌳