Olive, Vitex or Crape Myrtle. Which is best?

Q. You helped me out a couple of years ago when I had questions about growing tree roses.  Now I would like your opinion on some tree varieties. This fall I would like to replace a couple of sumacs in my back yard. I really like three trees: olive, chaste and crape myrtle but I can't find anything online that compares these three trees.  Do you have a favorite?  Can you give me some pro's and con's compared to each other?

A. These three trees are dramatically different from one another in many ways, are used for different purposes in the landscape and have different watering requirements. All three will work here, Crape Myrtle being more difficult to manage than Olive or Vitex.

Crape myrtle growing in desert soil

Comparing all three trees, crape Myrtle provides the most year around beauty in the landscape. All of them are relatively slow in getting some size so you might shop for some larger trees if you want some instant impact after their planting.

Olive is the only evergreen tree in the group. I would classify European olive as primarily a 25 to 35 ft. shade tree that can take tremendous abuse. This tree will rebound if pruned badly so it is a relatively safe tree to have if you contract blow and go landscapers to do your property.

The other two trees will not rebound like an olive if they are pruned badly. In my opinion, Crape Myrtle might be ruined.

If you need something that creates shade, screens, or privacy all year round and is easy on water use, then you might consider olive. As you know we can only plant so-called fruitless olive in Clark County, Nevada. So you will be restricted to either Swan Hill or Wilsonii. However, you can add Monrovia nursery’s Majestic Beauty (Monher variety) to the fruitless list as well.

I have had numerous complaints about fruitless varieties producing fruit as they get older. It is believed this happens because these are grafted varieties and the top is lost at the bud union. The rootstock continues growing which is a fruitful olive and the tree becomes an olive tree that produces fruit with a fruitless tag. Others believe tags are mixed up in the nursery.

Crape myrtle trunk, young tree

In any case, don't expect your fruitless olive to be totally fruitless. If you need this tree to be totally fruitless, pick something else. Olive is relatively pest free. It requires minimal maintenance.

Both olive and Crape Myrtle get to be similar in mature size, around 25 to 40 feet. It will do well in a lawn or a rock mulch desert landscape. You would use this tree if you want a rock solid landscape tree that can handle a lot of abuse.

Crape Myrtle can also be spelled Crêpe Myrtle. In other parts of the country they come in a wide range of mature sizes ranging from 3 feet tall to 25 feet tall. Their flower color ranges from white to pink's, to reds, two lavenders.

Selection in Las Vegas will be much more limited but shop around. I have been surprised seeing selections in Lowe's and Home Depot. It is flat-out gorgeous tree if cared for properly. That is the key.

European olive

It is what we call a specimen tree, a showstopper when in bloom and even in the winter when it is leafless. It is meant to be a focal point for landscape. A larger tree will provide shade as it gets older but it is really meant to stimulate conversations and to draw your eye because it says, “Look at me!” when it is blooming.

Olive flowers

Crape Myrtle is a beautiful tree when it is blooming but I would argue that the texture of its trunk and its silhouette in winter rivals its flowers. The exfoliating character of the trunk is gorgeous up close.

If pruned properly its winter silhouette without leaves can be beautiful as well. The combination of flowers and uniqueness of its trunk and winter silhouette provides year around beauty.

This tree needs to be pruned professionally by certified arborists or by a knowledgeable homeowner. You do not want blow and go landscapers to touch this tree!

It will require special fertilizer applications including iron. It will do best with wood surface mulches but it can grow in desert landscapes as well. In desert/rock landscapes crape Myrtle will require more care to keep it looking good over the years.

There are dwarf varieties 3 to 6 feet tall, semi-dwarf varieties 7 or 8 feet tall, all the way up to full size which is about 25 feet in height. Most sold here are full-sized but shop around and you may get lucky finding other types.

Locally I have had complaints that trees were mislabeled and customers received a different flower color from what they expected. The other complaint was how they were planted.

Be very careful of companies that advertise free planting. This tree needs to have plenty of soil amendment go into the planting hole at the time of planting. When planting is free, the holes are dug way too small, very little soil amendment is used and the type of soil amendment used his lousy.

If I were buying a boxed, specimen Crape Myrtle I would want to see that the flower color matched the nursery tag and I would have the hole dug to my specifications by an outside party and buy my soil amendment separately from the plant purchase.

I would be placing this near a patio, a sitting area outside the master bedroom, near a place for people congregate in the backyard, or where you want people to look in the front yard. It has few pest problems.

Vitex or Chaste tree is a smaller tree than the other two. None of the three trees are trees that originate from deserts. However, all three will perform in a desert landscape reasonably well.

Vitex in bloom

On the positive side of Vitex is its flowers. It is sometimes called the Lilac chaste tree because it's floral display does resemble lilac and it is a good alternative to lilac in hot deserts.

Vitex is considered to be either a large shrub or small flowering tree. It can be grown either way. When in bloom it does attract butterflies with flowers ranging in color from lavender to mauve to off white or light pink.

Vitex in winter form

However there are some newer varieties with the improved floral color and with very long flower spikes up to 12 inches in length. You will have to look around for these superior varieties. There are just too many to list but a partial list can be found at http://www.plantintroductions.com/vitexanewbeginning.html  

The leaves and seeds are aromatic. It must be pruned carefully when young to give it good form or its winter look may not be the best. It can look kind of ratty in the winter if not pruned well.

It is good in a dry landscape, a show stopper from May to about September. Use as summer focal point. Few pest problems but could be damaged by blow and go landscapers if allowed to prune it.