THE GARDENERS' CHRONICLE OF AMERICA. 
477 
SOIL FERTILITY AND VEGETABLE CROP. 
By Prof. Henry Bell, Illinois.* 
HP HE yield of vegetables is cut short at least one- 
third on account of lack of attention to the supply 
of plantfood for the growng crops. Vegetable crops, 
both in the greenhouse and in the garden, more 
than any crop, require most thorough attention to soil 
tillage and plantfood if they are to make maximum 
growth. The factors influencing productiveness may be 
classed under two headings — those influencing the home 
of the plant and those influencing the food. 
Soil drainage is absolutely essential to plant growth. 
Water-logged soil smothers the growing plant and the 
soil bacteria. 
There is great need for more attention to humus. Hu- 
mus is decaying vegetable matter in the soil. It performs 
four great functions : First, it helps hold water, catch- 
ing it like a sponge; second, it opens up heavy clay soils 
and binds together sandy soils ; third, it forms a home 
for the food of soil bacteria; fourth, it catches and ab- 
sorbs plantfood that would otherwise leach out of the 
soil, and saves it for the growing crop. 
A great deal of water is essential to successful plant 
growth, because the plant must have all of its food in 
soup-like form, with the exception of carbon, which it 
takes out of the air in a gaseous form, but it obtains all 
the rest dissolved in the soil water or root juices from the 
soil. In order to control the water supply of the soil, the 
gardener should aim to keep up the organic matter, and 
deeply plow his soil in the fall so as to create a reservoir 
for catching and holding the precipitation of fall, winter 
and early spring. His crops should be carefully tilled, 
so as to preserve a dust mulch which prevents the escape 
of soil water. 
A great deal of study is being given to the use of lime. 
Lime is not a plantfood, but is a soil corrector. It cor- 
rects a condition that we call sourness in the soil. Sour- 
ness is deadly to soil bacteria, both those that grow free 
in the soil and those that grow on the roots of peas, 
beans and other legumes. The soil should be kept suf- 
ficiently sweet so that its own constituents of plantfood 
may be able to serve the needs of the crops. 
The plantfood question is one of the most seriotis that 
the market gardener has to face. In order to meet the 
situation most successfully, he should inform himself as 
fully as possible relative to the moisture of the soil, the 
duties of the constituents of plantfood, and the best 
method of obtaining and handling them. The former 
great source of plantfood was manure. The gardener 
finds that he has to supplement his failing supply of 
manure with fertilizers, which are carriers of available 
plantfood. They supply three essential constituents ; 
Nitrogen, which causes rapid stalk growth and lengthens 
the season of growth of the crop ; phosphoric acid, which 
hastens the ripening and assists in the filling out of the 
fruit : and potash, which strengthens the stalk, influences 
the formation of starch in the fruit, and has a great deal 
to do with the healthy development of the plant. Fer- 
tilizers supply these three constituents of plantfood just 
as does barn manure. Fertilizers vary in analyses, and 
hence should be chosen of an analysis to suit the especial 
conditions of the soil and to meet the especial require- 
ments of the crop on which they are to be used. For in- 
stance a bean crop, which is harvested when the beans 
are ripe, under normal conditions should be fed with a 
plantfood very high in phosphoric acid, since it is this 
constituent as well as a medium amount of nitrogen and 
patash which the bean plant requires. On the other hand, 
the potato crop, under normal conditions, should be fed 
a liberal supply of available nitrogen and potash and a 
fair supply of phosphoric acid, since the nature of the 
crop demands that it receive a plantfood which aids in 
depositing starch in the tuber. 
For a quick growing crop, such as lettuce, radishes, 
or tomatoes, he should supply a fertilizer whose plant- 
food is rapidly available so that the plant can take it up 
and make maximum growth in the shortest time. For 
longer growing crops such as potatoes, beets, carrots, 
and the like, the fertilizer should contain a form of plant- 
food which is less rapidly available, so that the effect of 
the supply of food will last throughout the growing 
season. 
With proper attention to the preparation of the soil 
and balancing of plantfood, coupled with the use of high 
quality seed of suitable varieties, the yields of many of 
the truck and. garden crops can be increased very ma- 
terially. The secret is that the grower must inform him- 
self, and must lie carefully observant, benefiting by his 
yearly experience. 
^Extracts of address hefnve Chicago Convention of Vegetable Growers* 
Association til" America, b\ Prof. II. G. Hell. 
FORTIFY IN FALL AGAINST PLANT DISEASE. 
By Karl Langenbeck, Washington 
C< 'ME plant diseases have their seat in the soil. Our 
readers have been made familiar by us that scab intro- 
duced by infected seed potatoes may develop in such 
a soil not planted again with potatoes for several years 
and yet ruin later plantings. The scab germ thrives best 
in a soil kept over-sweetened. We have told how the 
earth may lie freed from the pest and still bring up the 
soil to full growing condition in several seasons by 
progressive sweetening, a little more in each season, al- 
ways using only sterlized seed. This cannot be done with 
a system of keeping excessive lime in the soil, as recom- 
mended with ground limestone. It must be done with 
the quick action of a short ration of quick lime or hydrate 
alternating with the natural souring resulting from man- 
ure decay. Excess of ground limestone will keep the 
field a scab seed lied. 
Rut, another soil disease has been spreading with rapid 
strides over the count ry. This is a vegetable cancer 
which attacks cabbage, cauliflower, turnips, radishes and 
Brussels sprouts. If not destroyed, it develops in the 
soil for years and attacks later crops. But as it attacks 
certain weeds, like wild mustard, a field never planted 
with these vegetables, may be badly infected with it and 
show only when these vegetables are grown. The name 
of the disease is club root, or "fingers and toes," from 
the way it looks on the crippled plant. But the mother 
germ of the disease, as it grows in the soil, is a living 
creeping slime, known to plant disease specialists as a 
"protista." Burned lime alone in sufficient abundance 
withers and destroys it. Nothing else will. For this 
sterlizing process, a liberal lime treatment is essential, 
and it is necessary to get the soil well stirred with ground 
lime before any material slaking of the lime can occur. 
From two to three tons per acre must be used, and con- 
trary to the usual practice in soil sweetening, it should 
be worked in with light plowing pr the cultivator and 
harrow. This must be done some months before replant- 
ing, and the Autumn is the essential time, so as to be 
safe for the next season. The cold of Winter assures 
the work of destruction done by the quick lime. 
