The Grey Leaves of our Desert

If you live in the desert, you may already know this, but if you didn't, this post may help you out with plant choices for your Tucson garden.  Do you ever notice that large green leaf plants have a harder time surviving our summer heat than their smaller grey leaf counterparts? Look closely at the leaves and you'll discover several things like tiny "hairs" or a waxy coating.   The grey leaf plants like a Texas Ranger or lavender both thrive and survive due to some interesting adaptations.  And it's for these reasons that these plants do extrememly well in our Tucson climate.

I found this explanation best explained by Jane Edmanson in Australia.  Why Australia?  Many species of plants do well here in Tucson from this part of the world.  If you head over to the Boyce Thompson Arboretum, there is an entire garden area dedicated to these uniquely adapted plants for our Sonoran desert landscape. Native is still the best, but there are certainly other choices out there for the avid gardener.  "Collectively, many of the plants with bluish grey, silver, even white coloured leaves, are known as grey leaf plants.  Another interesting characteristic of many of these grey leaf plants is the leaves can be hairy. Both the hairs and the waxy surface help reflect sunlight. The more sunlight that's reflected from a plant, the less water it needs for its functions, and the better it copes with drier conditions. The sides are reflective and the hairs trap a layer of humidity above the surface of the leaf to further reduce water loss. Another way that plants can reduce water loss is related to the waxy coating on their leaves. It’s on the outer surface, and means the plant uses less water and copes with dry conditions. A perfect example is Eucalyptus caesia which is sometimes called ‘Silver Princess'. It has a beautiful grey bloom on the branches, the leaves are greyish blue and capped by pinkish red buds that birds love. So many of the grey leaf plants are decorative and provide a welcome contrast to green plants in the garden. Their drought tolerance makes them practical in dry times, and with water restrictions, mean it’s possible to have colour and interest in the garden." Source: Gardening Australia

In the fern garden from last year.

Additionally many of these plants make excellent choices for moonlight gardens.  Here is a post I wrote this past year on how to create this magical type of garden. Creating a Moonlight Garden So if you've ever wondered why your silver grey leaf plants seem to perform better during our extremely dry and hot summer months, you now know:) It's good to mix the different colored leaves in for contrast. More tomorrow as we head back into the desert for ideas....

The Eucalyptus looks amazing next to the Arizona Ash tree in summer and fall. Taken last year in 2010

PS. Gray or Grey?  While writing this post, I became confused.  I've always written "grey".  Here's the spelling explanation.  grAy=American; grEy=English