Hot Gardens Newsletter - fast growing trees, how to plant bearded Iris correctly

Hot Gardens Newsletter: November

Preparing for winter in dry gardens

Cold Air, Warm Soil. After a long, sizzling hot summer, temperatures have dropped abruptly, signaling winter is at our doorsteps. If your garden is below the 4000 foot level you may still have time to install trees and shrubs to give them a head start for next year. While our air temperatures are now cooler, the ground is still warmer than it will be in early Spring, so plant now.

If you are above the 4000 foot level, winter is here–or on the way–so wait until next Spring for major landscape installation. Everyone–whatever altitude you live at–should add mulch to flower beds and around trees and shrubs now!

Fast growing, drought-tolerant trees

Chitalpa blooms Jack in the Beanstalk trees. In the children’s story, the magic beanstalk sprouted and grew sky-high overnight. While we cannot promise you instant, tall, shade-giving trees, there are some that grow fairly fast. The Chitalpa (Chitalpa x tashkentensis) will grow 2 feet or more every year to a mature height of 25 to 30 feet. Better yet, this heat-loving tree blooms with pink, white or lavender flowers all summer long.

Another fast grower is the majestic Chinese elm (Ulmus parvifolia). It can reach 30 feet tall within 5 years and ultimately can grow to a height of 40 to 60 feet. It has a graceful weeping shape, as does the Nichol’s Willow-leaf Peppermint tree (Eucalyptus nicholii). Again, you can count on growth of 2 feet or more per year with this low-water usage eucalyptus which grows to 50 feet tall. The bark is reddish-brown and the leaves, when crushed, smell like peppermint! You can find a list of more trees that will grow fast in our southwest desert climate on Fast Growing Trees.

Transforming a fountain

Spouting Off. If you are considering disconnecting your expensive fountain forever because of water restrictions or drought, you don’t have to remove it or leave it standing bare. It can be easily transformed into a beautiful container for plants to give you seasonal color. Combine flowering annuals such as purple, lavender and white petunias with trailing ones such as the chartreuse-leafed sweet potato vine. Or plant the sturdy perennial multi-color Lantana. Plant densely for the most dramatic effect. If you intend to keep your fountain as a water feature, remember to run it frequently, if only for a short time, to prevent damage to the pipes and pump from lack of use.

Love of bearded iris

Iris Love. We have to confess to a passion for Bearded iris (Iridacese) and if you act quickly there is still time to plant rhizomes for fabulous blooms next year. Plant them shallowly, just below the surface. After the flowers fade, the upright leaves continue to give a vertical structure to a garden border. Iris thrive in the sun and do not like “wet feet”. The Bearded iris is a low water usage plant, except for those water-guzzling, repeat bloomers that flower in both Spring and Fall. Consider combining iris with scented Geraniums (Pelargonium) for a perennial border that remains gray-green year ‘round and can survive some neglect.

Almost Native. Our efforts to grow a bougainvillea this year produced so-so results and old-timers promise us that our struggling plant will freeze and die over winter in our Mojave desert garden. (Those of you in the Sonora desert, in and around Phoenix, will probably have better luck.) But a low-water usage climber that has bloomed profusely in yellow, gold and orange for months is the Trumpet creeper, a native of South Africa that acts like a local. It needs support and can grow to 30 feet in one season. It can also be used as a ground cover on a steep, dry slope. As with virtually all low water usage plants, it will need regular watering until it is established.