June 2008
How's Your Garden?

How's Your Garden?

By Lois Trigg Chaplin

World’s Hardiest Palm is Native to Alabama

If you’ve ever come across a small, clumping palm in the woods in the southern half of the state, you may have found a native specimen of needle palm (Rhapidophyllum hystrix). Not to be confused with palmetto, needle palm has finer, more deeply cut and darker green fronds, and is surely distinguishable by sharp, six-inch long, dark spines or "needles" growing at the base of its stems. These are often hidden by leaves piled up in the needles, so be careful as you plunder around the base of the palm to look for this surefire ID.

Needle palm is believed to be the most cold-hardy of all palms, with specimens surviving temperatures of zero degrees or lower. The photograph you see here came from a garden in Oklahoma City. Slow-growing needle palm eventually forms a large clump at least six-feet tall and equally wide (no single trunk).

If you want to try a palm in your yard, you should certainly grow this one. It makes a beautiful landscape specimen; just give it plenty of space to spread as it ages because it won’t be fun to dig up. Compared to other palms, it is more shade tolerant, too. And like other palms, it is relatively drought-tolerant when well-established.

The place to look for needle palm is at a nursery specializing in natives or a garden center offering a good selection of natives. Plants will likely be small and relatively expensive compared to common tropical palms, but, of course, will live much longer in frosty areas.

Should you be a little nutty about palms and other tropicals, you may be interested in the activities of the Southeastern Palm Society. Visit their website as www.sepalms.org. The name of the organization is misleading because it also brings together enthusiasts of many types of tropical plants and citrus, providing cutting edge information and testing of their northern limits. The organization has quarterly meetings and garden tours that bring together enthusiasts from various states.

Do You Visit Gardens When You Travel?

Most gardeners like to see what grows in other parts of the country. If that’s you, check out membership in the American Horticultural Society (AHS). Dues are a tax-deductible $35 a year ($50 per couple) and entitle you to free admission or other discounts at more than 200 gardens and institutions throughout the U.S., plus a few in Canada and the Virgin Islands. You can download a list of gardens with "reciprocal admission" at www.ahs.org/events/reciprocal_events.htm. Membership also entitles you to a nice bi-monthly color publication, The American Gardener, which is sure to expand your plant and gardening knowledge. Alabama gardens who participate in offering AHS member-benefits include Huntsville Botanic Garden, Dothan Area Botanical Garden, Mobile Botanical Gardens, Aldridge Gardens and Birmingham Botanical Gardens.
Let the Parsleyworm Eat

This big, colorful caterpillar, called a parsleyworm, that may be feasting on your dill, fennel, parsley or rue is the caterpillar of our native black swallowtail butterfly. They love these herbs and some gardeners plant plenty just to attract them. Parsleyworms like to feed on plants in the carrot family, which also includes our native Queen Anne’s lace. After the caterpillars reach full-size (about 2 inches), they will move to another spot to pupate and emerge as beautiful black swallowtails in a few weeks. The black swallowtail is native throughout the U.S. and Southern Canada. Invite them to your garden by having plenty of their favorite food on hand.

Control Water to Soaker Hoses

Soaker hoses are known to be a great way to reduce the total amount of water needed to water a vegetables, flowers or new shrubs. You may already have several. Sometimes you can reduce water use even more by making sure your soakers are working only on the plants that really need it. For example, last year I planted my tomatoes really deep, so they had an excellent and deep-root system and did not need watering quite as often as the big-leaved, more shallow-rooted squash in the garden. So I put a water distributor on the soaker hoses to each row allowing me to control the flow of water to each as it is needed. These distributors are available at most hardware and big box stores carrying watering supplies.

Monitor the Drought

Although we’ve had some relief by rain, at the time of this writing nearly all of Alabama was still under some stage of drought. Chances are you’ve chosen more drought-tolerant flowers for beds this year; lots of succulents, ornamental grasses, geraniums and perhaps containers by the door that are easy to water with a bucket from the shower. Keep up with changes in the drought situation at www.usdroughtmonitor.com.


Watch out for whiteflies on gardenias. While working on my Southern Gardeners Book of Lists, one nurseryman jokingly suggested a list: "Which Gardenias Get the Most Whitefly," which would be all of them, of course. Nevertheless, the fragrance of these shrubs makes them worth growing. So, if you see those tiny, moth-like, whiteflies swarm out from a shrub when you disturb the leaves, take a few minutes and spray the foliage, especially the underside, with summer oil. Because insects breathe though their skin (cuticle), it is important to coat the underside of leaves thoroughly to get any eggs and immature forms attached there. You may miss some adults that fly off while you spray, so more than one spray is usually best.

Lois Trigg Chaplin is author of The Southern Garderner’s Book of Lists and former Garden Editor of Southern Living Magazine.