6 Colorado Experiment Station 
or waste cotton and wool, which mats may be bought from the dealers. 
Good mats may be had at from $1.00 to $1.50 each and will last a long 
time. Satisfactory coverings may be made by stuffing burlap covers 
with straw. Ordinary gunny sacks, horse-blankets, boards or any other 
convenient covering may be used. 
It is not advisable to leave the covering over the plants any more 
than necessary, as it causes them to become spindly and yellow from 
lack of light. When, the plants have been covered for a considerable 
length of time, light should be admitted gradually, as too sudden ex¬ 
posure to sunlight might be fatal to them. 
During very cold weather, it is also helpful to bank up the sides 
and ends of the frame with manure. 
Handling Manure 
The best manure for hotbeds is from grainf-fed horses or mules. 
It should contain about one-third of its bulk of straw, hay or leaves. 
The manure should be carefully handled in collecting to prevent exces¬ 
sive decomposition. 
About two weeks before time for seeding the hotbed, the manure 
should be hauled to it and piled in a flat, compact heap 3 to 5 feet high 
near the hotbed. If the weather is very cold, several buckets of warm 
water may be added to start the manure to heating. In four or five 
days the pile should be well heated thruout. It should then be turned 
inside out, putting the coldest manure on the inside of the heap. When 
the manure has again heated, the pit should be filled. In filling the 
pit, put in layers about 6 inches at a time and tramp well, especially 
around the edges of the pit. If the manure is not moist enough, warm 
water should be sprinkled over each layer. Enough manure has been 
used when the pit lacks about 4 inches of being full after the manure 
has been well tramped. The sashes should be put on and left until the 
manure has thoroly warmed up, when the soil may be put in. The 
heating period of a hotbed is usually 8 to 10 weeks. When this is over, 
the bed may be continued as a coldframe. 
Soil 
Good garden loam soil should be used for hotbeds. Four inches 
of soil is enough for most plants grown in the hotbed, but root crops 
such as radishes need five or six inches. As the soil is put in, it 
should be well pulverized, packed and leveled. When this has been 
completed, it should be watered, if necessary, and the sashes again put 
on. 
Seeding 
For several days after the manure is put in the temperature rises, 
often going above 125° F. It then begins to fall. When it has lower¬ 
ed to 90° or 85°, the seed may be planted. 
