Vol. LV. No. 2405. 
NEW YORK, FEBRUARY 29, 1896. 
SI.00 PER YEAR. 
COLD FACTS ABOUT HOTHOUSE LETTUCE. 
A FAVORITE CROP FOR GLASS GARDENING. 
Seed, Soil, Varieties and Markets. 
In any garden work, and this is especially true of 
the winter garden, the secret of success is to have 
something on the ground constantly. It costs but 
little more to have some plants half grown and ready 
to take the place of the first crop when marketed, 
than it does to devote the whole house to a crop and 
then wait several weeks for the next to come on. In 
case of plants not readily handled, “ catch crops” 
may be grown in the interim. 
From three to four months are required for lettuce 
to attain the best condition for marketing, though 
with somewhat strong bottom heat, we have taken off 
a crop in 10 weeks from the time the seed was sown. 
So in growing lettuce for the winter markets, the 
seed for the first crop should be started as early as 
September 1, and other sowings should be made at in¬ 
tervals of about a 
month to insure a 
constant supply. 
We usually sow 
the seed in light, 
rich soil in flats— 
shallow boxes 
about 16 x 20 
inches and two 
inches deep—and 
place the flats in 
a moderately 
warm and well- 
ventilated room 
to induce rapid 
growth. A house 
kept at a night 
temperature of 
about 50 degrees 
is pref erred. 
When the first 
true leaves are 
well started, 
prick out the 
young plants 
about 2x2 inches 
in other flats or 
in a shallow bed. 
Water carefully, 
and stir the 
soil frequently. 
About three or 
four weeks later, 
transfer to the 
permanent bed 
placing the 
plants about 6x6 
or 8x8 inches—the distance varying with the variety 
grown. Many successful growers practice handling 
twice before the final transfer, placing the young 
plants two inches apart at the first handling, and four 
inches at the second. With the second and third 
crops, this is, doubtless, a good practice, as the main 
body of the house is thus more fully utilized. 
The soil into which the plants are put at the second 
transfer and at the final handling, is usually some¬ 
what heavier than that used at first. We generally 
take one part of rotted sods or rich garden loam, and 
one part compost or well-rotted stable manure. On 
solid beds, we also place a layer of fresh stable 
manure before putting in the soil ; thus having, in 
effect, a large hotbed in the house. Before the second 
crop is put on the bed, the soil is enriched by a liberal 
quantity of stable manure, which is thoroughly 
forked in. The photograph shown at Fig. 45, rep¬ 
resents our lettuce house as seen in January. The 
upper bench is often used for radishes, and the lower 
one for carrying forward young plants ; though, as 
in the present instance, the latter is sometimes de¬ 
voted to the use of students. 
To be of the best quality, lettuce must be grown 
rapidly, and the one element needful in securing rapid 
growth of foliage is nitrogen. This element we often 
supply in the form of nitrate of soda. Place about 
three ounces—a small handful—of the nitrate in a 12- 
quart can of water and sprinkle the soil thoroughly. 
It is, perhaps, needless for us to say that to apply the 
nitrate at the rate of 100 pounds per acre, the can of 
water should be distributed over a space about nine 
feet square (81.6 square feet). During the earlier 
stages of growth, the plants may be watered freely 
with a coarse spray ; but as the heads begin to form, 
and the leaves cover the surface of the ground, we 
usually water with a solid stream between the plants. 
Not infrequently the heading of the plants seems to 
be hastened by an occasional application of warm 
water, and this may well be used when applying the 
nitrate of soda. The marked success of the method 
of sub-irrigation already outlined, will, no doubt, 
completely change existing methods of treatment in 
this direction. In any case, the atmosphere should 
be kept moist by frequent spraying of walks. The 
leaf surface of the lettuce plant is enormous, and the 
rapid transpiration in case the atmosphere is very 
dry, will often seriously injure the plants. 
The temperature of the lettuce house may be varied 
considerably, though most growers prefer a night 
temperature of about 45 degrees, and a range of about 
20 degrees during the day. In case it is desired to 
hold a crop in cheek for some special purpose, the 
house may be kept 10 degrees lower than here in¬ 
dicated. On the other hand, we often force the crop 
for a short time by increasing- the heat. But in gen¬ 
eral, the conditions of temperature should be as 
nearly uniform as possible. 
Insect and fungous enemies must be watched most 
closely. It is a good plan to strew tobacco stems or 
tobacco dust on the bed among the plants; and 
thorough fumigation once or twice a week is indis¬ 
pensable. It is much easier to keep the aphis from 
gaining a foothold than it is to rid the house of this 
pest when once well established. Whenever a plant 
is affected with mildew, it should at once be removed, 
and the use of sulphur on the steam pipes is recom¬ 
mended. But if the soil is stirred frequently, and 
there is reasonable care in watering and in maintain¬ 
ing a uniform temperature, we are seldom troubled 
with mildew. One of the advantages claimed for the 
practice of sub-irrigation is that there is less liability 
of trouble from this disease. 
The most profitable varieties to grow will depend 
entirely on the markets available. In New England, 
there is little demand for any but the cabbage let¬ 
tuces, while in the Western markets, the open-head 
or curled leaf varieties are sought. Of the former 
type, there is nothing better than the old White- 
seeded Tennis Ball, or a selected strain o'f this known 
as Rawson’s Hot¬ 
house. Of the 
second type, 
Grand Rapids is 
the most popular, 
though Curled 
Simpson is good. 
The cabbage let¬ 
tuces are some¬ 
what more diffi¬ 
cult to grow than 
the others, and 
usually command 
a corresponding¬ 
ly higher price. 
It is difficult to 
give any general 
notes on market¬ 
ing, as conditions 
vary so widely in 
different sections 
In the West, 
heads weighing 
two ounces aver¬ 
age about 20 
cents per dozen 
at wholesale, 
while those 
weighing four 
and six ounces 
will bring 40 to 50 
cents in early 
winter and late 
spring. In Feb¬ 
ruary and March, 
the prices are 
about double the 
above. Tn Boston and other Eastern markets, the 
prices range from 60 cents to 81 per dozen heads, and 
often higher. The heads are cut off at the surface of 
the ground, and packed in barrels or in bushel crates, 
and then shipped. The demand is best and the prices 
highest in February and March, so the grower should 
aim to have his heaviest crop mature at that time. 
For a beginner in greenhouse gardening, lettuce is 
one of the most satisfactory crops to grow. It is 
easily managed ; requires a smaller outlay for a suit¬ 
able house than is necessary for cucumbers or toma¬ 
toes ; it is always in demand, and is not a total loss 
if not marketed within a certain limited time. 
To summarize : From three to four months are re¬ 
quired to perfect a crop of lettuce. The seed should 
be started in flats as early as September 1, and suc¬ 
cessive sowings should be made at intervals of about 
one month. Use rich soil ; transplant frequently ; 
cultivate freely; use care in watering; watch con¬ 
stantly for mildew ; prevent rather than destroy the 
INTERIOR OF A LETTUCE nOUSE. now THE CROP IS GROWN. Fig. 45. 
