Lagerstroemia

The first thing we need to talk about when discussion Lagerstroemia is its flowers. Without a doubt, they are the tree’s most attractive feature. Flowering appears in the summer, beginning at the end of May–beginning of July and lasting until October at the latest. The flowers appear in heavy clusters at the ends of new branches that have grown since spring. Lagerstroemia’s flowers are very diverse and range from different shades of white to pink, purple and red. The flowers can be dense or relatively sparse. Proper pruning of the flower clusters once they have fully grown will encourage additional waves of flowering. Some cultivars of Lagerstroemia will grow additional waves of flowers without requiring any pruning. Truly outstanding cultivars will have 4–5 waves of flowers a season or will have prolonged waves of flowering. We recommend pruning the fruit at the end of the flowering season to encourage further growth and additional waves of flowering. Such pruning will also encourage later and more attractive fall displays.

Another element that creates great variety and interest between the different Lagerstroemia cultivars is the foliage. Lagerstroemia’s foliage is varied in size, density and color. The leaves’ color are different when blooming, in maturity and in their fall display. There are Lagerstroemia trees with reddish blooms and green leaves, green blooms and purple leaves, purplish blooms and green leaves and other combination. The different colors of leaves together with the variety of flowers create spectacular and especially attractive displays. Lagerstroemia’s varied fall displays are in all the colors of fire. Note that there are cultivars with dark foliage whose leaves tend to curl up, which creates a less vital and even sickly appearance.

The Lagerstroemia trunk is also an important ornamental element. The colors of the trunk vary from cultivar to cultivar. Some trunks are light-colored, some peel and reveal red hues that call to mind the colors of the Arbutus trunk. The peeling look is very reminiscent of eucalyptus trunks. A good example of this is the old white cultivar, ‘Natchez,’ whose trunk is a very attractive ornamental element. Our nursery also has a new hybrid cultivar that we are developing that has a “mottled” trunk in colors of gray and red. Lagerstroemia naturally has anywhere from 3–8 trunks, which form a magnificent and very impressive tree. This shrub-like appearance does not prevent designing a higher crown, which makes Lagerstroemia suitable for various uses. Lagerstroemia indica responds well to pruning. Lagerstroemia can easily be designed with a single trunk, which makes it suitable for even more uses, such as traffic islands, smaller gardens, streets and more. In general, Lagerstroemia is very well-suited as a street tree, and it is used as such across the country. Remember that its height does not exceed 8 meters, making it a relatively small tree. Its advantages are clear: Lagerstroemia does not interfere with paving nor is it especially messy (beyond its falling flowers and the leaves it sheds in autumn). It has no juicy fruits that attract birds, sully sidewalks or create slipping hazards. It is well-suited for all parts of the country in terms of climate, and when planting a row originating from the same clone, the flowers and fall display will be particularly uniform and impressive.

After having listed Lagerstroemia indica’s many significant ornamental advantages, we should also mention the challenges it poses to give the whole picture. In the Israeli climate, Lagerstroemia positively thrives, and it generally does not have pests or diseases like it does in other climes. Lagerstroemia indica’s main challenge in this regard is powdery mildew, which afflicts it, and which may harm not only its appearance but also cause its degeneration. Powdery mildew appears in very humid regions and less in drier areas such as the mountains and desert. It can be avoided by the location the tree is planted – and ensuring that it is planted in full sunlight. This will prevent powdery mildew. It is also important to ensure proper watering so that significant surplus water does not accumulate and create an excessively moist environment due to evaporation. Preventive care can be performed at the end of spring or beginning of summer. Another important recommendation is to use outstanding cultivars that have been checked and tested for their resistance to powdery mildew.

It’s important to note, however, that no Lagerstroemia indica exists that is immune to powdery mildew. All cultivars of Lagerstroemia indica are under threat from powdery mildew; they are only differentiated by their degree of sensitivity. We have found that cultivars with red leaves are much more sensitive to powdery mildew than those with green foliage. Some examples of the outstanding cultivars with significantly reduced sensitivity to powdery mildew are ‘Natchez,’ ‘Muskogee,’ ‘Bella Mia,’ which we have developed in our nursery, and ‘Lunar Magic,’ which is exclusive to Ilan Nursery.

Another challenge is the matter of grafting. A selected clone on a rootstock creates a superior, outstanding and uniform plant that preserves the preferred properties cultivated in that clone and that requires minimal maintenance. In the case of Lagerstroemia, to preserve the properties of genetically outstanding cultivars, vegetative propagation is recommended, but in this case, rooting is preferred over grafting. Grafted Lagerstroemia is a tree that requires regular, intensive maintenance because the rootstock may take over the scion, and then you encounter all kinds of Lagerstroemia hybrids with different colors. And that’s the best-case scenario. In the worst case, the entire grafted plant degenerates. Unfortunately, in Israel there is insufficient awareness and logistical ability to keep up this maintenance of cleaning unwanted offshoots and branch stubs so we would recommend buying plants with grafting at a low point or from the roots. It’s important to consider that when Lagerstroemia is rooted, it takes longer to grow (which is reflected in the growth time and the price), but it results in a better plant than grafting, one that is generally strong and durable with an optimal lifespan. Unfortunately, this matter has not yet been sufficiently assimilated in the Israeli market, and as a result, many grafted Lagerstroemia trees that have been planted do not reach maturity and are not thriving.