Aglaonema was first introduced into the Florida foliage plant industry in the 1930s in the form of Aglaonema Modestum, the Chinese Evergreen. This plant was the primary Aglaonema grown until the 1960s when many of the present-day cultivars were introduced.
Production of Aglaonema has increased from I percent of total foliage plant production in 1967 to an estimated 5 percent in 1980, displacing other foliage plants in the total mixture at an increasing rate. Reasons for increased production include greater consumer demand for Aglaonema due to its tolerance of interior environments; increased availability of production information on culture, pest and disease control; and greatly improved availability of cuttings and divisions from Central and South American sources.
The origin of commercially grown aglaonemas is southeast Asia. This source has supplied the parents used to breed many of the cultivars presently on the market. The type of growing conditions preferred by aglaonemas includes relatively high soil (70-80F) and air (80-9019 temperatures, moist soil, and low light (10002500 foot- candles) intensity.
Most of the common cultivars of Aglaonema grown commercially in Florida are briefly described below:
Aglaonema can be propagated by seed, tip or cane cuttings and division.
Seed-can be used to propagate A. Commutatum and its cultivars, but no other cultivars. When fruit turns bright red, it is ripe and should be harvested, cleaned of pulp and planted. Seeds should be planted in sphagnum peat or sphagnum moss at a depth of one half inch, maintained at a temperature of 70- 80oF and kept moist. Germination normally takes 1 to 3 months, although fresh seed may germinate in 2 weeks. At lower medium temperatures, germination percentage may be low and takes longer. At present, information is not available regarding storage of seed; however, it is known that seeds lose viability rapidly and should be planted as soon as possible after harvest.
Tip cuttings-are most commonly used to propagate Aglaonema. Cuttings should be harvested with at least 3, but preferably 5 or more leaves . in general, 3-leaf cuttings do not root or grow as well after potting as those with 5 or 6 leaves. Cuttings root well in a peat, peat-perlite or peat-styrofoam medium, when pH is adjusted to 5.5 to 6.0. Liquid fertilizer in the form of 20-20-20 applied at 2 pounds per 100 gallons per 400 square feet when roots start to form will improve root and plant quality. The temperature of the rooting medium must be 70-800F for plants to root in 4 to 6 weeks. If rooting medium temperature is in the range of 60-650F, rooting may take 10 to 12 weeks. The misting cycle during rooting should be set for 15 seconds of mist per each 30 minutes during daylight hours. it is best to space cuttings so they are not severely crowded; about 3 by 3 inches for most cultivars.
Cane cuttings-although not commonly used to grow aglaonema commercially, are a means to propagate many plants from a few stock plants. Divide each cane into as many sections as there are buds (eyes), or leave 2 buds per cane piece if they are very close together. Place cane sections in a propagation bench prepared as listed for tip cuttings but do not mist. Cane pieces should be spaced about 1 inch apart and barely covered with the propagation medium. Once roots have formed and buds start to grow, apply 20-20-20 liquid fertilizer once a month until plants are large enough to transplant; usually 4 to 6 months.
Division-of cultivars that produce large numbers of suckers such as Fransher Evergreen and Silver Queen Evergreen is another method of propagation. Recently, these divisions or clumps have been imported in fairly large numbers and have been used to produce 8 to 10 inch pots. Clumps can be divided with a knife by cutting crowns so that several growing points
Numerous experiments on potting media for aglaonema have defined the needs of this plant while showing that there is no single "best" medium. Aglaonema requires a growing medium with high water holding capacity and excellent aeration, which is best obtained with one of the following mix combinations (listed as part by volume):
Other potting media may also be suitable for growing aglaonema provided the non-capillary pore space is 8 to 12 percent by volume and capillary pore space is 55 to 65 percent by volume.
At time of mixing, incorporate sufficient dolomite into the potting medium to raise the pH to 5.5 to 6.0 Usually 7 to 10 pounds of dolomite per cubic yard will be adequatE to raise pH to the desired level. If pH is still not at the desired point supplement the dolomite with calcium carbonate or calcium hydroxide.
Aglaonema will grow on a wide variety of fertilizer sources, ratios and rates.
Sources-proven acceptable for aglaonema include liquid and slow release fertilizers. Based on information from other crops, it is suggested that the nitrogen source by composed of 50 percent NH (ammonia cal) nitrogen and 50 percent N03 (nitrate) nitrogen.
Ratios-proven to be acceptable for aglaonema include 1-1-1- and 3-1-2. Based on economics, a 3-1-2 ratio fertilizer such as a 9-3-6, 12-4-8, 18-612 or other analyses close to these will provide required nutrients at lowest price without adding unnecessary salts.
Rates-Numerous experiments have shown that excellent quality plants can be grown on 1200 pounds of nitrogen per acre per year in greenhouses (1400 pounds of nitrogen per acre per year is suggested in areas open to rainfall such as shade houses). Where soil temperatures cannot be maintained at 601F minimum, fertilizer rates can be decreased 25 percent as plants will not be actively growing.
Deficiency symptoms-Aglaonema has a high demand for copper, and a deficiency of this element will cause yellowing and distortion of terminal leaves on Fransher Evergreen, Silver Queen Evergreen and others, and in severe cases, cessation of growth. To prevent this problem, thoroughly mix three pounds of Perke per cubic yard or similar micronutrient mixture into the potting medium at time of mixing, drench with 12 ounces of STEM@ per 100 gallons as a post plant treatment or spray periodically with copper.
Tissue com position- Suggested optimum ranges of elements for aglaonema are as follows: nitrogen-2.5 to 3.5%; phosphorus-0.4 to 0.7%; potassium-1.5 to 2.5%; calcium-0.5 to 1.0%; magnesium-0.4 to 0.8%; boron-10 to 50 ppm; copper-10 to 60 ppm; iron-50 to 300 ppm; manganese-50 to 300 ppm; and zinc-25 to 200 ppm.
Best light intensity for aglaonema is between 1000 and 2500 foot-candles, depending upon temperature. Where day temperatures rarely exceed 951F, light intensities of 1500 to 2500 foot-candles will produce excellent plants. However, when a temperature of 1001F is common, a range of 1000 to 1500 foot- candles is desirable. Unlike most foliage plants, aglaonema positions its foliage according to the light intensity, thus when leaves are 45 degrees or more from the vertical, light intensity is satisfactory, while if less than 45 degrees, light is probably too high. Plants growing under excessive light usually have bleached foliage and slight tip burn.
Best growth of aglaonema is obtained when soil and air temperatures are relatively high. Soil temperatures between 70 and 80OoF are most desirable for root growth, while air temperature during the day should be at least 70oF and preferably 800oF. Night temperatures may range between 60 and 651oF, provided root temperatures above 650oF are maintained. If soils are allowed to become colder than 600F, almost all growth will cease.
Aglaonemas are likely to exhibit light green foliage and may develop copper deficiency of terminal leaves. This is especially true with Fransher Evergreen. Indications are that aglaonema is very inefficient in extracting copper and possibly several other micronutrients from the growing medium when soil temperatures are between 55 and 650oF. If temperatures drop below 500oF, chilling injury characterized by loss of the silvery color in Silver Queen Evergreen and others will occur. This problem is most severe where plants have been growing at a relatively high temperature prior to the cold period or where wind chill is a factor.
Greatest growth on aglaonema occurs when plants are watered frequently (2 to 3 times per week) and are grown in a well drained, highly aerated medium. Pot watering systems such as leader tubes or surface emitters are suggested to reduce foliage wetting and subsequent residue from the water. Plants grown in poorly drained and aerated potting media often grow slowly with a resulting 25 to 50 percent lengthening of production schedules. Growth in such media can be improved if plants are watered less frequently, but it is much easier to use the correct potting medium.
Several genera of nematodes especially species of lesion nematodes, Pratylenchus, and root-knot, Meloidogyne have been reported to limit growth of aglaonema. Plants infected with lesion nematodes are stunted and basal leaves chlorotic and drooping. Roots may be rotted and completely absent from the base of the plant while in less severe or less advanced infections, remaining roots exhibit dark, necrotic areas or lesions. Aglaonema infected with root-knot nematodes may exhibit similar foliar symptoms as with infections by lesion nematodes; however, infected roots will contain galls or swellings and sometimes root decay in serious infections. Nematodes need not become serious problems in production for growers who propagate from nematode- free stock. Use nematode-free media, grow on raised benches, and avoid nematode introductions by practicing sanitation. However, should a nematode problem be detected, the nernaticides Dasanitll (fensulfonthion) 15G at 6.7 pounds per 1000 square feet, TemikO (aldicarb) 10G at 2.3 pounds per 1000 square feet, and Mocape (ethoprop) 6EC at 1/2 to 1 pint of formulation mixed with enough water to cover 1000 square feet of bench area are labeled for use. Following application, rinse foliage and wet soil to a depth of 4 to 6 inches. (Note: Never apply granules to wetted foliage.) MocapO 6EC is labeled also as a pot drench treatment at the concentration of 1/2 pint in 100 gallons water and applied at 1/2 pint per 6 inch pot or 1 pint per 8 inch pot. Use caution to avoid foliage contact with the nernaticide mixture or wash off immediately with fresh water to avoid foliage injury. Phytotoxicity tests have indicated the safety of labeled concentrations of Mocae applied as 2 drenches at 3 month intervals to Aglaonema Commutatum.
Aglaonema does not appear to be seriously affected by insect, mite, or related pest problems with the possible exception of periodic infestations of caterpillars (larvae) of lepidopterous insects, root-infesting mealy bugs as well as aglaonema and latania scales. DipelO (Bacillus thuringiensis) 50WP is labeled for greenhouse use against lepidopterous larvae at 1/2 to 2 pounds per 100 gallons and a spreadersticker should be added to improve coverage and persistence of foliar residues. DiazinonO 50W at 2 pounds per 100 gallons and SpectracideO (diazinon) at 2 quarts per 100 gallons of water and applied as a soil drench are registered in Florida for control of root mealybugs on greenhouse and field-grown foliage plants. The insecticide, OrtheneO (acephate) 75S is labeled for use on greenhouse foliage plants at 2/3 pounds per 100 gallons of water for control of scale crawlers.
Aglaonema is almost as disease- free as pest-free, provided it is grown properly. The best way to grow this plant is to use correct potting media, light, fertilizer and water levels and to apply water at the surface of the potting medium.
Numerous foliar diseases have been reported on aglaonema, but the only serious problems involve the bacterial pathogens Erwinia and Xanthomonas. Both diseases can be controlled by keeping the foliage dry (avoid overhead watering). KocideO 101 or Agri Strep can be used to reduce losses due to these diseases. Both diseases are prevalent on cuttings imported from Central and South America with symptom expression occurring during the propagation period; however, once cuttings are rooted and foliage allowed to dry' these disease problems do not appear on new foliage.
Soil borne diseases which rot roots and occasionally stems are primarily caused by Pythium and Rhizoctonia. Control of these organisms is most easily accomplished by pasteurizing potting media, growing on raised benches, and using well drained, aerated media. If root rot symptoms persist, use of chemical controls are warranted. Drenching pots with a combination of Trut)anO (ethanol) 30WP and Benlatee (benomyl) 50WP at 12 ounces and 8 ounces respectively in 100 gallons of water or BanroV) (ethanol plus thiophanate methyl) 15-26WP at 8 to 12 ounces will aid control. The volume of solution applied to a pot depends on the type of container: 1/4 pint per square foot is suggested for mini pots or shallow flats; I pint per square foot for pots less than 4 inches in diameter or beds less than 4 inches in depth; and 11/2 to 2 pints per square foot for pots greater than 4 inches in diameter or beds deeper than 4 inches.
Culture of aglaonema is less variable than one might expect. Cuttings can be started in a propagation bench or direct stuck in pots. Several production regimes are listed in Table 1.
Table 1. Production systems for 6 inch aglaonema.
*Use of a single cutting in a 6 inch pot requires use of cultivars with a bottom breaking habit such as Fransher, Silver Queen, Silver King and Ribbon Evergreens.
Growers who grow their own stock plants in benches can expect to produce 20 to 30 cuttings per square foot per year for most varieties, although Malay Beauty Evergreen and White Rajah Evergreen have typically low yields and Fransher and Silver Queen Evergreens have high yields.
Most aglaonemas are grown in 6 inch pots, but 8 inch are also becoming popular. The same system of production can be used for 8 inch as for 6 inch, but production time is about 2 to 3 months longer.
NOTE: Trade names are mentioned with the understanding that no discrimination is intended and no endorsement is given by the Institute of Food and Agricultural Sciences.