The Second half of meteorological summer:
Well, contrary to the constant predictions of the NOAA climate service that we would be warmer than normal this summer that has yet to pan out. In fact, we had a much wetter than normal June and it was not lost on anyone when June gloom lasted into the second week of July. Thats about to change. It might be late but the dry season is upon us. That means that we will have a net loss of moisture from the landscape until fall rains resume. And that could be late this year. More NOAA forecasts are pointing to a warm dry autumn, whether that comes to pass (considering the cold, not the predicted warm start to summer) so, we could have hot weather extending into September. Not a prediction but a just a note. We’ve been as hot as 105ºF (1987) in September.
Real heat has yet to show
A few more notes on the first half of meteorological summer. We’ve hit 90ºF only two times so far once in May (91º) and once in June (93ºF). We average 14 days above 90ºF annually. In recent years we’ve quickly accumulated a large amount of these days before July 15th. (2018 holds the record with 36 days above 90ºF total) So, for what its worth it looks like we’re in for an average summer. That means that if you like pleasant, dry, warm, clear weather with no humidity and mild evenings you will be happy to be in Oregon
Lagerstroemia ‘Play it Again’. Also, our warmest (hottest) weather is traditionally the last week of July and the first week of August. And that is just beyond the reach of forecasts. As of today NOAA is forecasting highs in the low to mid 90’s next Monday-Tuesday. Our hottest weather so far.
The secret to a bloomy Crape myrtle
Speaking of heat this dovetails nicely with an experiment that I’ve been conducting involving my Crape myrtles. For the past two years, despite more than enough summer heat many trees have been disappointing in bloom. At first I considered that the trees were not receiving enough water in summer. However, I began watering mine in June and continued until August. Though my trees responded with some growth their bloom was still somewhat disappointing. The one variable that is the same for the past several springs is that they have been extraordinarily dry. What this means is that just as the trees were breaking dormancy they were deprived of water. It seems that this does not make a very happy crape myrtle. In fact, drought stressed crape myrtles first lose the glossy shine to their leaves and when leaves lose luster and go dull the tree has gone into a kind of sleepy dormancy. This occurs far in advance of wilting. To break this spell it takes a lot of water and heat which accumulate to bring the tree into bloom. And depending on when you realize this and irrigate with gusto the window of time can close too. The tree will bud out just in time for fall color.
Don’t just stare at the Crape Myrtle, BE the Crape myrtle.
This year I began watering my Crape myrtles as soon as they leafed out. I kept them well irrigated (a deep soak once a week) and the results have been spectacular. It seems that there is a third variable in making crape myrtles bloom. I once thought it was heat + water and the duration of heat that was alone responsible for spurring them into bloom. Now I know that consistency (consistent irrigation) is the the third variable and this should begin just as the plant is waking up. It seems that if you never let the plant become drought stressed it just continues to grow leaf, and then quickly bloom. I have 25 Crape myrtles in my garden and this very cool (below average) summer the majority of my trees are about to go into full bloom-NOW regardless of the lack of heat. It appears momentum is just as important. Some varieties that responded well to this method are: ‘Yuma’, ‘Hopi’, ‘Pecos’, ‘Tuscarora’, ‘Acoma’, ‘Pink Velour’, and ‘Wichita’. So, if you’ve been disappointed with the bloom of your crape myrtle follow my advice. Begin watering the tree as soon as it begins to show leaves (sometime between late April and mid-May). It may seem inordinately early but stick with it. A deep soak once a week and maintain irrigation into summer and this consistent supply will reap consistent growth and a much improved flower set too.
Also, the older the tree the earlier and more precocious it will be in bloom ( over 10 years old) and it will bloom much earlier.
Ideal companions for planting beneath Crape myrtles:
Hardy Fuchsias, dwarf Rhododendrons. Hellebores, Vancouveria, Epimedium. Hosta, All of these perennials benefit greatly from a blast of sun until the Lagerstroemia eventually leaf out and cast shade.
Its a Covid, Covid Summer….
We will be continuing curbside pick up for the foreseeable future. We are going to let science decide when we open back to the public. Things at the moment are too uncertain.
One thing that we’ve begun to love is what we call fence shopping. We are so lucky that the majority of our nursery can be viewed through the fence. We are more than happy to help customers in this way. We’ll happily bring plants to customers for better viewing and this also helps the employees be more responsive to the customer as well. We like it. Please wear a mask and maintain the required social distancing.
Have a wonderful dry season and may your garden thrive.
Paul