This section is from the book "Commercial Gardening Vol4", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
These are not infrequently first cousins. Aided by the constant use of the syringe and the stuffiness of the houses mildew will spread like wild-fire. A drier overhead method of treatment, freer ventilation, the abolition of the syringe, and, finally, little or no mildew. For early winter forcing, start the plants in a temperature of 45° F. and increase to 55° F. for Hybrid Perpetuals and to 60° F. for Hybrid Teas about six weeks later.