Post by violetlover on Oct 8, 2004 7:06:33 GMT -5
GENERAL GROWING INFORMATION
The African violet (Saintpaulia) is an excellent flowering house plant which will grow and flower under low light intensities found in the average home. Where there is insufficient natural light, they can be grown and flowered successfully entirely under artificial light. Large numbers of different varieties, types and colors available, and the ease with which they can be propagated make this an excellent plant for interior decoration of the home.
African violets require about 1000 foot-candles of light for 8 to 12 hours per day for best growth and flowering. However, lower light levels for longer periods of time are also satisfactory. Often, it is possible to tell from their appearance whether light levels are satisfactory. If light is too low, leaves are usually deeper in color and thinner than leaves on plants receiving higher levels of diffused light. Unless light is extremely low, plants may grow well but will flower poorly or not at all. In such instances, supplemental artificial light is helpful in promoting flowering.
Excessive light levels cause leaves to be pale or yellowish green, much lighter than normal and some leaves may show dark areas where they have been shaded by other leaves. Growth at high light levels is slowed and plants become more compact, however, although flowering may continue freely for a while it will eventually decrease due to chlorophyll destruction.
The length of time plants are exposed to light also affects growth and flowering. Plants may receive proper light levels for only several hours a day and thus insufficient total light while plants in another location receive light of lower intensity but for longer periods of the day, and thus more total light. African violets should not be exposed to direct sunlight.
African violets can be successfully grown when the only source of light is from fluorescent lamps. Although incandescent lamps may be used, fluorescent lamps give better results, are less expensive to operate, and produce less heat. Plants grown entirely under fluorescent light should receive approximately 600 foot-candles of light for about 12-14 hours per day. This amount of light can be provided by suspending two 40-watt fluorescent tubes 12 to 15 inches above plants. Tubes should be mounted in suitable fixtures equipped with reflectors.
African violets grow best at a night temperature of 65 to 70°F, but will grow satisfactorily at 60 to 80° F. If possible, place plants in the coolest place in the home during these periods or in an air conditioned room.
African violets tolerate dry air, but need higher humidity for best growth and flowering. Humidity around plants can be increased by setting pots in water-tight metal or plastic trays filled with wet pebbles or sand. Care must be taken to avoid placing pots directly in water to prevent root damage.
Drainage is one of the most important considerations in preparing a soil mixture for African violets. An excellent mixture of readily available materials may be prepared by mixing equal parts (by volume) of soil, sphagnum peat, and horticultural grade perlite. Excellent plants can also be grown in mixtures consisting of equal parts of sphagnum peat moss and perlite. Commercially prepared packaged soil mixtures are also available for African violets. Soil mixtures should have a pH of about 6.0 to 6.5 or be slightly acid for best results.
Sterilize soil and used pots before planting to kill disease organisms, insects, nematodes and weed seeds that may be present. If the suggested soil mixture is used, only the soil need be sterilized, since new sphagnum peat and perlite are usually sterile. Most commercially prepared soil mixtures are sterilized. Soils may be sterilized by placing in a container and heating in an oven. For best results soil should be slightly moist before sterilization and heated to 180 degrees Fahrenheit and held at that temperature for 30 minutes. Old clay pots may be sterilized by the same procedure used for soil. Plastic pots will not withstand heat sterilization, but can be re-used after washing thoroughly with soap and water or a dilute chlorox solution.
The African violet (Saintpaulia) is an excellent flowering house plant which will grow and flower under low light intensities found in the average home. Where there is insufficient natural light, they can be grown and flowered successfully entirely under artificial light. Large numbers of different varieties, types and colors available, and the ease with which they can be propagated make this an excellent plant for interior decoration of the home.
African violets require about 1000 foot-candles of light for 8 to 12 hours per day for best growth and flowering. However, lower light levels for longer periods of time are also satisfactory. Often, it is possible to tell from their appearance whether light levels are satisfactory. If light is too low, leaves are usually deeper in color and thinner than leaves on plants receiving higher levels of diffused light. Unless light is extremely low, plants may grow well but will flower poorly or not at all. In such instances, supplemental artificial light is helpful in promoting flowering.
Excessive light levels cause leaves to be pale or yellowish green, much lighter than normal and some leaves may show dark areas where they have been shaded by other leaves. Growth at high light levels is slowed and plants become more compact, however, although flowering may continue freely for a while it will eventually decrease due to chlorophyll destruction.
The length of time plants are exposed to light also affects growth and flowering. Plants may receive proper light levels for only several hours a day and thus insufficient total light while plants in another location receive light of lower intensity but for longer periods of the day, and thus more total light. African violets should not be exposed to direct sunlight.
African violets can be successfully grown when the only source of light is from fluorescent lamps. Although incandescent lamps may be used, fluorescent lamps give better results, are less expensive to operate, and produce less heat. Plants grown entirely under fluorescent light should receive approximately 600 foot-candles of light for about 12-14 hours per day. This amount of light can be provided by suspending two 40-watt fluorescent tubes 12 to 15 inches above plants. Tubes should be mounted in suitable fixtures equipped with reflectors.
African violets grow best at a night temperature of 65 to 70°F, but will grow satisfactorily at 60 to 80° F. If possible, place plants in the coolest place in the home during these periods or in an air conditioned room.
African violets tolerate dry air, but need higher humidity for best growth and flowering. Humidity around plants can be increased by setting pots in water-tight metal or plastic trays filled with wet pebbles or sand. Care must be taken to avoid placing pots directly in water to prevent root damage.
Drainage is one of the most important considerations in preparing a soil mixture for African violets. An excellent mixture of readily available materials may be prepared by mixing equal parts (by volume) of soil, sphagnum peat, and horticultural grade perlite. Excellent plants can also be grown in mixtures consisting of equal parts of sphagnum peat moss and perlite. Commercially prepared packaged soil mixtures are also available for African violets. Soil mixtures should have a pH of about 6.0 to 6.5 or be slightly acid for best results.
Sterilize soil and used pots before planting to kill disease organisms, insects, nematodes and weed seeds that may be present. If the suggested soil mixture is used, only the soil need be sterilized, since new sphagnum peat and perlite are usually sterile. Most commercially prepared soil mixtures are sterilized. Soils may be sterilized by placing in a container and heating in an oven. For best results soil should be slightly moist before sterilization and heated to 180 degrees Fahrenheit and held at that temperature for 30 minutes. Old clay pots may be sterilized by the same procedure used for soil. Plastic pots will not withstand heat sterilization, but can be re-used after washing thoroughly with soap and water or a dilute chlorox solution.