African Violet

AFRICAN VIOLET Gesneriaceae Saint Paulia Species

HABITAT: Native to Central Africa.

USES: Houseplants.

HABIT:  Thousands of varieties exist exhibiting differences in foliage, shape, color, and texture.  The year round clusters of velvety 1-2 inch pink, blue, purple, white, and bi-colored flowers all accented by yellow pollen-bearing stamens are borne in 5 petal singles and many petal doubles that form with smooth, ruffled or frilled edges, above the usually hairy green to bronze foliage which may also be velvety, smooth, scalloped, wavy, lance or heart-shaped and variegated.  Plants are usually 4-6 inches tall.

SEED GERMINATION AND CULTURE: Sow the fine seed on Park's Grow Mix.  DO NOT COVER.  Keep moist and germinate under lights, if possible, with the lights being placed 3-4 inches from the seeds and used at the rate of 20 watts per square foot for 24 hours per day.  Maintain a warm temperature within the soil medium of 70° during the germination period which requires generally 20-25 days.  Some varieties continue to germinate for several weeks to months.  Transplant the small seedlings when large enough to handle (usually within 5-6 weeks) to 2 1/4 inch peat pots, then shift to larger pots (4 inch) when roots emerge from pot walls.  Maintain lights on a 12-14 hour per day basis at 3 to 4 inches from the seedlings to give them sturdy, vigorous growth.  From seed to flower:  6-12 months. African Violets thrive in bright, indirect, or curtain filtered sunlight although as light intensity increases during summer months, it may be advisable to shift  locations of plant to an east or even north exposure.  Plants also thrive under 14-16 hours of artificial light per day with night temperatures of 65-70° as ideal. Pot up in 1 part commercially prepared potting soil and 2 parts peat moss and 1 part of coarse sand.  Packaged potting soils alone are also satisfactory.  Plants must have excellent drainage.  Set the pot on a pebble-filled tray of water, being careful that the water does not touch the pot bottom, to offer increased humidity.  Dry air causes leaf curl and bud drop.  Keep African Violets barely moist and fertilize every month with a standard house plant fertilizer of low nitrogen content.  Set plants with crown (where roots and top meet) slightly above the soil line and provide plants with good air circulation.  For best results, water with warm water (cold water spots the foliage). Pot African Violets in as small a pot as possible due to their liking of tight quarters.  African Violets have a normal resting period after flowering at which time feeding should be withheld.  When rooting leaves, use leaves from the middle of the plant as the older outer leaves rot easily due to their hardness.  Divide when several small plants form around the crown.  To keep plants rounded in shape, turn the pots periodically.  Dust collecting on the hairy leaves can be removed with soft camel's hair brush. Plants will enjoy a brief period outdoors when weather has warmed.  Place them where there is complete protection from winds and driving rains and direct sun.  Plunge pots to their rims in the ground.  Fertilize every 2 weeks.  Bring indoors about Labor Day.

SPECIES:  S. ananiensis:  Low growing miniature creeper.  Very small convex, heart-shaped, plaited, green leaves covered with gray hairs.  Small violet-blue flowers.
S. confusa - S. Kewensis (Usambara Violet) Miniature:  Light green thin leaves with long toothed margins covered with flattened, not erect, hairs.  Silver green undersides.  Small medium blue flowers with darker violet center.
S. difficilis:  Robust.  Long stemmed, light yellow-green, thin quilted leaves with saw-tooth margins.  Many light violet-blue, dark eyed flowers with bright yellow anthers.
S. diplotricha:  1 inch round flowers, sky blue.  Quilted, incurved, thick leaves bronzy above the reddish/purple beneath.
S. intermedia:  Creeping.  2 inch purplish-green leaves with silvery gray felt covering reddish undersides.  Margins saw-toothed with long bent hairs.  Pretty medium blue flowers with violet eye.
S. ionantha (African Violet):  Robust with large flowers of light violet blue.  Prolific.  Dark coppery-green, hairy 2-3 inch leaves with reddish undersides.  Thousands of varieties available.
S. magungensis:  Creeping with procumbent brown stems and 1 1/2 inch to 2 1/2 inch rounded convex green leaves with pressed veins.  Pale green undersides.  Small medium blue flowers with darker eye.  Good hanging basket plant.
S. nitida:  Small rosetted dark green, almost hairless, waxy leaves rounded and lightly cupped.  1 inch violet blue.
S. orbicularis:  Upright, weak with thin light green, red rounded leaves having depressed veins.  Long thin brown stems.  Small pale lavender blue flowers with dark purple centers.  Somewhat shy bloomer.
S. pendula:  Robust, spreading with creeping strong stems and light green rounded cupped, plate-like pliable leaves covered with erect long hairs and notched margins.  Pale green undersides.  Medium blue flowers.
S. rupicola (Kenya Violet):  Robust.  Light green, heart-shaped glossy leaves covered with erect hairs.  Whitish undersides.  Prolific single wisteria blue flowers.
S. velutina:  Shapely, dwarf with small thin 2 inch leaves, blackish velvety green above and reddish/purple beneath, covered with many short erect hairs.  Tiny deep violet flowers often tipped with white.

PROBLEMS:  Loss of Vigor:  Lack of fertilizer.  Underwatering.  Too much or too little light.
Nematodes:  Loss of foliage.  Color dull.  Outer leaves droop.  New leaves emerge damaged.  Fewer flowers.  Center of plant loose in pot.
Foliar Nematodes:  Center stops growing.  Veins appear swollen.  Lower leaves show a triangular spotting.
Mites:  Center light green.  Smallest leaves sickly gray or yellow/green.  Buds, blossoms, and stems distorted.  Dwarf growth.  Bunched centers.  Hairiness more pronounced.  Buds drop prematurely.
Cyclamen Mites:  Leaves curl upward and are brittle.
  Broad Mites:  Leaves curl downward.
Spider Mites:  Silky cobwebs stretch from leaf to leaf or cover flowers.  Foliage is gray or reddish brown, mottled or speckled.
Stunt:  Leaves shorter and broader than normal.  Thickened, brittle, rolled up margins.  Young leaves more affected.  Shinier look.
Mealy Bug:  Dusty look.  Stems of leaves have a grayish, webby look.  Cottony masses appear deep in crown.
Soil Mealy Bug:  Plant wilts, limp leaves are dull.  Leaves small in center.  Buds cease to form or increase.
Thrips:  Whitish spots on foliage.  Blotches in dead areas on leaf edges.  Leaves may wilt and fall.  Occasionally small reddish spots.  White streaked flowers.  Malformed and premature bud and blossom drop.
Overwatering or Crown Rot:  A previously healthy plant flops and long outer leaves drop over pot edges.  Watering fails to revive.
Petiole or Flower Rot:  Leaf stalks (older leaves) become jelly-like when they droop and touch pot edges.  Stalks shrivel and collapse.  (Plants normally discard oldest leaves which gradually yellow and wither.)
Yellow Rings on Upper Leaf Surfaces:  Ring spot (water with tepid or warm water).
Bleached Leaves:  Too much light, too low fertility, lack of trace elements.  Try a chelated fertilizer.
Brittle Leaves:  Lack of magnesium or sulfur or both.  Added rotted leaf mold helps.
Brown Centers:  Over fertilizing, water settling in crown.
Brown Leaf Spots:  Water getting into center of leaves or using cold water.
Buds, No Flowers:  Low humidity, insects, lack of calcium.
Buds Dry Up:  Low humidity, poor air circulation, sudden change of environment.
Bunched, Tight Centers:  Chilled, over exposed to flourescent lights, (place paler green varieties at the end of the tubes rather than lamp centers).
Double Trouble - When Doubles Produces Less Than Singles:  Increase light, increase humidity, increase feeding (twice that of singles), increase water slightly.  Covering plants with plastic at night may stimulate better bloom.
Mites:  Gnarled growth.
Leaf Stalks Rot:  Petiole rot.  Dip rim in paraffin before planting.  Cover rim with foil.
Long-Necked Plants:  Poor culture.  Lack of light.  Older leaves normally do this.

INSECTS: Aphids, Mealy Bugs:  Use an approved insecticide, such as Malathion.
Snails, Slugs:  Clean up debris.  Use Metaldehyde Bait.
Red Spider Mites, Cyclamen Mites:  Use an approved insecticide such as Malathion, Diazinon.
Nematodes:  Use sterilized potting mixes.
Fungus Gnats:  Spray soil with Malathion.
Thrips:  Use an approved insecticide such as Malathion, Diazinon.

DISEASES:  Botrytis:  Increase air circulation.  Lower humidity.  Dust with Captan twice weekly.
Blight:  Spray with Bordeaux Mixture every 7-10 days.
Damping Off:  Sterilize soil with Chloropicrin.  Dust with Captan.
Crown Rot:  Treat soil with Terrachlor.
Stunt, Virus:  Destroy plants.  No chemical control.
Powdery Mildew:  Spray with dormant lime sulfur before buds break.  Use Benlate.
Ring Spot:  Destroy infected plants.  Use Malathion on insects.

PROPAGATION:  Leaf cuttings, crown divisions, seeds.