a hose. The plants need to have the foliage sprayed and it does not spot the foliage if no 
sun falls on the foliage before they dry off. If late in morning cover plants with news- 
papers after watering, until dry. The interval between waterings should be long enough 
to permit the top soil to become slightly dry. 
Very many advise to set the pots in a pan of tepid water, and to remove when the 
surface becomes moist. This is an allowable practice but it requires supplementary pro- 
cedures. One must sometimes spray the foliage and also water from the top of pot part 
of the time. Culture advice for any house plant usually says, “Be sure the drainage is 
perfect.” But sub-irrigation does not result in perfect drainage. Not enough water is 
likely to drain away when removed from a pan of water. Most of us must use hard water 
containing soluble alkaline or other salts. When subirrigated these salts remain in the 
soil and are added to by each irrigation. Nearly all cultivated plants, particularly shade 
loving plants, require some leaching of the soil to remove excess soluble salts. Continued 
too long, subirrigation may raise the soil pH sufficiently to stop flowering. 
Good ventilation is needed by all plants but Saintpaulias do not like drafts. Slow 
movement of air currents are more conducive to their comfort. 
Soil formulae. Some growers sell prepared soils. Probably they are nearly all good. 
But the plants have a considerable tolerance and do well in a wide variety of soils. They 
should be at least mildly acid in reaction and a type that will drain easily and quickly. 
Heavy clay soils, therefore are not good. 
We use about one half oak or redwood leaf mould and one half sandy loam or good 
loose garden loam. To this is added enough sponge rock or coarse sand to make the soil 
gritty and aid drainage. Fine screened peat is as good or better than leaf mould. It is not 
at all necessary to buy prepared soils. 
Fertilizers. We use only Spoonit and recommend it to be applied once a month, on 
a day following watering. 
Sun exposure. Most of the advice one receives over-emphasizes shade. Lack of suf- 
ficient light intensity seems to us to be one of the most frequent causes of non-blooming. 
All shade plants need a certain amount of modified sunlight to make them flower. In 
the winter, the sun is at a low declination. Its rays must pass thru several times the thick- 
ness of atmosphere penetrated at noon in the summer when the sun is directly above or 
at “high declination.” Very little shading is needed on the greenhouse in winter. Treated» 
thus our. plants bloom profusely all winter. Very likely, plants in a south window, any- 
where in the north temperate zone, in winters, will be sufficiently shaded by a thin 
muslin curtain. Remove the curtain on dark days. 
But summer sun is much stronger. One must give more shade. It should not, how- 
ever, be too heavy. The plants need much light. The color of the foliage will tell you 
what they can endure. When healthy plants have light, yellowish foliage they probably 
receive too much sun. Medium green is about right. Very dark green foliage indicates 
insufficient light and lack of flowers corroborates it. 
Humidity. Saintpaulias bloom better in a relative humidity of 60% to 70% altho they 
live and appear healthy at a much lower degree. At this moment the humidity of our 
violet house is 62%. In our kitchen, it is 28% at 80° temperature. In other rooms it 
would be lower. Heated rooms are likely to be 25% relative humidity or less, at times. 
It would be uncomfortable for us to live in a room sufficiently humid for violets. One 
can localize a higher humidity around the plants by setting the pots over a saucer con- 
taining gravel and sand and filled with water which does not quite touch the pots. Mrs. 
Rector’s book, “How To Grow African Violets,’ (see Garden Reference Books) suggests 
a tray made from a chick feeder, with wire guards removed. Many sizes are available at 
feed stores. In thé bottom place sand, gravel or coke with water. Plants set in these trays 
will have a sufficiently humid atmosphere. 
Pests. Be sure to keep your plants free of insect pests. One of the most common on 
house plants is the mealy bug. Examine plants frequently for pests. Mealy bugs look like 
tiny specks of cotton. One way to remove and kill them is to use a bit of cotton on end 
of a toothpick. Dip the cotton in alcohol and pick off the bugs. Do not touch foliage 
with the alcohol. , 
Ly, 
