132 
VEGETABLE GARDENING 
It is always better to sow after rain rather than before, 
and this is especially true in the heavier soils. The soil 
soon bakes after a rain, and a hard surface crust is fatal 
to the germination of delicate seeds. Such crusts ex- 
clude air, and thus prevent the necessary physical and 
chemical changes in the soil, and make it difficult for the 
tiny plant to force its way through the soil to the light. 
If heavy rains fall soon after sowing, the crust can often 
be broken to advantage by rolling as soon as the ground 
is dry enough. It is usually desirable to sow in freshly 
stirred soil, because of better moisture conditions. 
192. Quantity of seed to sow. — Many questions must 
be taken into account when determining the proper 
amount of seed to use on a given area. Among them 
may oe mentioned: (1) The viability of the seed or its 
power to grow. This should be previously determined, 
and the rate of sowing regulated accordingly. (2) The 
date of sowing. It may pay to take chances in planting 
some crops, as beans and sweet corn, before the ground 
is warm enough to make certain of a high percentage of 
germination. By using seed freely a good stand may be 
secured (3) The physical character of the soil. More 
seed should be used in heavy soils, because the percent- 
age of germination will be necessarily less than in light 
soils. (4) The size or vigor of the young plants. Carrot 
and parsnip seedlings are very delicate and feeble; and 
many may be lost before they are well started. There- 
fore the safe practice is to insure a good stand by heavy 
seeding. (5) If to be transplanted, the time when this 
work will be done should be considered. The seed may 
be sown much more freely if transplanting is to occur in 
about three weeks from sowing. (6) The demand of the 
market. At times the market may demand small carrots, 
onions and other products, or exactly the reverse, and 
sowing must be regulated accordingly. (7) It is rather 
expensive to thin some crops. For example, the thinning 
