Weekly Express-News Article

By Calvin R. Finch, PhD, SAWS Water Resources Director, and Horticulturist

Saturday, August 30, 2008

 “Sago Palms”

            Sago palms are not really palms.  They look like a small palm, but they are a cycad.  Cycads are primitive cone bearing relatives of conifers.  In South Texas and other climates where temperatures rarely fall below 20°F, Sagos are used as container plants or in beds as ornamental plants that give the patio or pool area a tropical look.  Sagos look good on the patio as individual specimens or surrounded by other containers with light-colored blooms that contrast with the dark green foliage. 

 

            They are slow growing to ten feet tall with frond like leaves that emerge from a growing point at the top of the trunk.  The larger size specimens can be very expensive.  Some of the most impressive specimens in area gardens are protected from cold by their own greenhouse structure.

 

            Sago palms will tolerate sun, but seem to do best in partial shade such as on a patio with an Eastern exposure that is shaded from the Western sun.  Sagos are very tough in terms of survival, but the foliage often reacts to changes in season and light exposure by yellowing of some leaves.  During some rain periods a leaf spot also shows up.  The plants grow through both problems as long as we do not over react by adding excessive amounts of fertilizer or water, neither of which the hardy Sagos require.

 

            Scale can also show up on Sago palms.  If the population of scale is allowed to grow large, the leaves can lose their dark green color and appear faded and speckled with yellow.  Scale is something most gardeners forget about, because it is so discrete.  If you see faded speckled leaves, rub your fingernail over the back of the leaflet and leaf rib.  If there are grayish bumps that come loose with the fingernail rubbing, you have scale insects that are sucking the juices from the plant.

 

            The usual way to kill scale is to apply a horticultural oil which suffocates the scale within its calcium shell.  Good control requires good coverage of the insect.  Speed up the control by mixing acephate with the horticultural oil.  Whichever treatment you use, the scale will not drop off immediately.

 

            Cycads like Sago palm have male and female plants.  The male produces a central cone like-structures with scales.  The female fruiting body starts with feathery organs that eventually produce smooth, red seeds shaped like, but slightly smaller than Brazil nuts.  The cone and seed stalk are very interesting to observe if you decide to allow them to complete the process, or you can cut them off to let the plant concentrate on leaf formation.  Sago palms also reproduce vegetatively.  “Pups” are produced at the base of the plant.  They can be allowed to produce another stem for the parent plant or they can be removed to start another plant. 

 

            Treat the pups like a palm transplant.  Remove it with a sharp shovel or even a machete and after letting the wound cure for a week, place it in a container of potting soil.  The healed bottom can be pushed into the soil, but should not be planted deeply.  Prop the pup up with stakes so the base can eventually send out roots into the potting soil.  Rooting hormone is not necessary and do not use any fertilizer.  Water sparingly when the soil dries to two inches into the container.  Place the pup and its container in partial shade.