Deciding whether you’re using the right fertilizer in your garden
depends on what you’re using and which crop you are using it
on.

Vegetables are classified into three categories as to their
nutrient requirements:

• Heavy: cabbage, Irish potatoes, lettuce, onions, sweet
  potatoes, tomatoes.




• Medium: herbs, asparagus, okra, beans, green peas,
  beets, pepper, cantaloupes, pumpkin, carrots, radish, corn,
  sweet, cucumbers, squash, eggplant, Swiss chard, watermelon and
  all greens.




• Light: Southern peas.

Fertilizer Labels

Fertilizer labels contain three numbers that correspond to the
percentage of nitrogen (N), phosphorous
(P₂0₅) and potassium
(K₂0) in the bag. The nutrients will always be listed
in this
order and in a ratio. A 10-10-10 fertilizer means it has equal
amounts of N, P and K. And 5-10-15 means there is twice as much P
as N and three times as much K as N.

Why should I buy fertilizer with lesser amounts of nutrients? Why
not just buy the highest analysis possible?

Think!

Not all of the plants in your garden are alike. Tomatoes flower
and produce fruit. Greens just produce leaves. Potatoes flower on
top and produce tubers underground.

Even Numbers for Greens

The even analysis (8-8-8, 10-10-10) is used mostly for
nonflowering or leafy plants such as lettuce and the greens
family. With these, you want to produce a lot of edible
foliage.

The other analysis (5-10-15, 4-8-12) is used to grow fruiting
plants such as tomatoes and peppers. The high first number is N
which produces vegetative growth.

Now, nothing is wrong with vegetative growth. You need it for the
leaves to produce chlorophyll for the plant. However, too much N,
especially at the wrong time, can cause the fruit on tomatoes and
peppers to fall off.

Tomato’s Main Concern

Remember, the tomato plant isn’t really interested in producing a
nice, big, juicy fruit for you to enjoy. It’s just trying to
produce seed to perpetuate itself.

In the grand scheme of things, putting out a high-N fertilizer
signals the fruiting plants to use this extra-N to grow
vegetatively. They will slough off their fruit and start growing
larger leaves at the expense of fruiting.

Timing the addition of N as a side-dressing is critical, too. The
plant needs fertility for growth, so put the fertilizer out at
planting. But don’t add any more until after the plant flowers
and the fruit grows to the size of a dime. Then side-dress with
extra nitrogen for the next fruit set.

In short, customize the fertilizer for the plant. The plant will
appreciate it.