While we’ve seen Christmas decorations in some stores, the Christmas holidays don’t feel real until our Thanksgiving leftovers are fully digested.
Poinsettias, especially in the Kona, Ka’u, and Kohala dryer, will soon have spectacular colors. Although mainland people consider the poinsettia to be a Christmas flower, for us it blooms from November to March. They are native to the drier parts of Mexico, so do best with less rain during their flowering season. The poinsettia, or Euphorbia pulcherrima, was introduced to the United States in 1828 by Joel Roberts Poinsett, botanist and first United States Ambassador to Mexico. There she is known as “La Flor de la Nochebuena” or Flower of the Holy Night. Today, Christmas wouldn’t be Christmas without the poinsettia.
So if you don’t have seeing supplies in your home and garden for Christmas, they are now available in stores, nurseries, and garden centers.
Buying potted stock at a garden center or nursery is the easiest way to establish holiday ornamental plantings. There are a number of poinsettias. They are available in traditional reds or you can enjoy color combinations indoors and in the garden if you mix red plantings with white and pink varieties.
Poinsettias will grow on a wide range of soils, including sand, rocky soils, and clay. Despite the great adaptability, plants will give you a better color show if you take good care of them.
In massed beds, the application of fertilizer is important. An application of fertilizer in August should now produce large, colorful bracts. Plants need repeated applications of fertilizer in early spring, again in June, and perhaps mid-summer if there is heavy rains.
For best results, prune poinsettias in late winter or early spring after flowering is complete. Cut them up to 12 to 18 inches from the ground.
You will find that a compact plant will provide more color than a plant with a few unbranched stems. To promote a riot of colorful bracts, prune the plants several times during the growing season. Pinch off new growth after it is 12 inches long, leaving four leaves on each shoot. Be sure to stop pruning in early September, as the flower buds will fall into place in early October.
Poinsettias show their color depending on the length of the day and temperature. A plant near a lighted window or lamppost often refuses to color like a neighboring plant in a darker corner nearby. Gloomy skies in September and early October will shorten the days, causing buds to form and plants to bloom before the holiday season.
You will find that temperature is a limiting factor for a good flower show. If nighttime temperatures are well above 70 degrees, bud formation will be delayed. Abnormal periods of hot weather during this critical time may not allow bud formation at all. The best flower development is when nighttime temperatures range from 60 to 68 degrees. This year has been a bit warm, low temperatures delay flower formation, but the highland areas have been ideal for a riot of color.
For the plants in your garden, a problem to watch out for now are mites. Drier conditions are ideal for this pest. Spraying an acaricide will take care of the little stinks. If you want to avoid spraying, it helps to water the leaves daily with the garden hose. It will also minimize whitefly attacks. Avoid watering in the heat of the day.
If you want to experiment with this year’s potted plant, don’t throw it away when the last leaf falls.
The plant will show brilliant colors in the upcoming Christmas season if you follow these tips. First, store the pot, plant, and all in a secluded place. This treatment is intended to force the plant to hibernate on cool days while the shriveled crown nourishes the dormant roots.
Water the plant only to prevent it from drying out. Avoid giving it fertilizer. Try to store the sleeping plant in the shaded corner of the carport.
Towards the end of February, tenderly wake up the plant by cutting off the dead top. You can grow the new plant in last season’s pot, but the poinsettia will be happier if you place it in the ground where it can flex its roots better than within the confines of a pot. Make sure to plant it where there will be plenty of sun and well-draining soil.
If you want to learn more about tropical gardening tips and techniques, consider becoming a UH master gardener. For more information, call 808-981-5199 at the Hilo Komohana Farm Complex or Ty McDonald in Kona at 322-4893.