If there is any excuse for shading it is just now in the hottest days, for the sake of the men who have to work in 120 degrees, or more, and the young plants that may have had their roots very slightly disturbed by planting. If you shade let it be only a very temporary kind. A lump of clay dissolved in a pail of water and thrown on with a dipper will do very well. It will wash off at the first rain, and then you want it off.
Weeds grow apace in this tropical heat, and it's a poor soil that won't grow weeds; they should be kept pulled, not only now, but should never be seen. There is no harm in a scratching over of the surface for a month or so after planting, but later the surface should not be disturbed; hand weeding should do it all.
The young plants will grow fast and there will be no trouble with mildew till the end of September, but from that time till steady firing begins is the most critical time, when we have slight frosts at night, or a rainy, cold day and night, and the next week a warm, sunny time with the thermometer at 80 degrees in the shade.
From the time the .roses are planted till frosts occur they can't possibly have too much ventilation. To digress a moment. We noticed in Philadelphia that they leave the end door open on a warm day in October, and we hear sometimes of side ventilation on roses. It may do in some localities, but it will never do with us. Bottom or side ventilation or an open door for any length of time would be fatal, because the draught would produce mildew, produce it to a certainty.
When the nights get down to 50 degrees outside you should have a little fire heat. Here is the advantage of steam, as you can let it in through one pipe; leave air on at night when this gentle fire heat is going. You don't want a high temperature, but you want a dry, healthy atmosphere. All along about this time when using any artificial heat try to keep the house down to 55 degrees, and just about this time put a dab of liver of sulphur on the pipes.
When there is little or no occasion for artificial heat in September and October is the most trying time for the man in charge, and with the greatest care mildew will often get a lodging. We used to put flour of sulphur mixed with linseed oil on the steam pipes, thinking its fumes could do no harm. Be careful about that. If you do it at all it must be only a small spot here and there. The dry sulphur blown on the leaves with a Peerless bellows is much safer, and syringe it off the first fine, sunny day. A strong smell of sulphur in the house will cause many of the mature leaves to turn yellow and drop, and, denuded of foliage, your plants cannot be vigorous. Be cautious of sulphur on steam pipes. On hot water pipes the fumes will be less strong and less dangerous.
There are times when from various causes you may not be able to fire till the end of October and have been without fire on chilly nights. By shutting up the rose houses tight on these nights you will notice in the morning the dewdrops in tiny beads on the edges of the pretty little leaves. If that continues for three or four nights you will have an attack of a fungus that is much worse than our common mildew: I have seen it take every young leaf off in a few days and actually kill the young red growth. You can easily distinguish it from mildew, for it shows on the young, tender leaves as distinct silver threads. A little fire and air would have errectually prevented this, but if you can't fire, then leave on air. Far better have the house cool and dry than cool, close and damp. I have learned what this fungus will do years ago, and have not forgotten it, for it touches our most sensitive organ, the pocket.
When steady firing commences the night temperature should be kept as near as possible to the right mark, as to which there is not much difference of opinion. Some growers like to keep higher than others. A reasonably low temperature means, fewer buds and higher quality, and a higher temperature means more buds and poorer quality. From 55 to 58 degrees at night for all the ordinary teas seems to be agreed upon, and I incline to the lower mark, believing that quality is better than quantity. American Beauty should have 60 degrees, and the useful crimson Meteor should have from 65 to 68 degrees. Without a high temperature the Meteor is useless in the coldest months.
Richmond is said to grow and flower freely in a Bridesmaid temperature, 56 to 58 degrees, one great advantage over the old Meteor, for every extra degree in winter means a bigger coal bill.
This fall at John H. Dunlop's, of Toronto, I saw some grand houses of roses ventilated by a thermostat, which was controlled by water pressure. He was delighted with it, and if it works perfectly it must be the thing, for it never forgets. You can of course set it to any degree. I will have more to say about ventilation in another chapter, but must say here that it is one of the most important parts of rose growing. Seventy at day would be a good temperature; when any above that ventilation should be given, and where the ventilators are continuous and open at the ridge it is much safer given than with a ventilator here and there that lets the cold wind in.
There may be days when there is a cold, cutting wind and the sun will raise the temperature of the house to 75 degrees, and it will be better to let it remain so than let in such a chilly blast. Again, there may be dull, damp, mild days, when it is better and proper to fire briskly and give air. An experienced gardener can tell at once whether a house is too chilly or too hot, whether the sashes are up too high or whether the atmosphere is too close. You ought to be a living, breathing thermostat, but if you were you could not divide yourself into twenty sections; and those gardening attributes are no more transmitted than the art of music or poetry or telling a story. So you must lay down a rule and your men must follow it to the best of their ability.