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Germinating Corn Seed

Posted by pehling | October 14, 2014

Do you have problems getting corn to come up? Uneven? Seeds Rot? In may not be your fault. It may be poor seed. There are several things you can do to get full rows.

Figure 1
Fig. A

Test the seed: The package will state that the seed is “packaged” for this year, but it does not state that the seed is fresh. Usually it contains a blend of new seed and seeds up to many years old. There can be a great variation in the vigor of seeds. New varieties are sometimes in short supply and some poor quality seeds may be sold.

Testing seed before you plant your garden is quite easy:

1. Soak 10 to 20 seeds overnight.
2. Dampen a paper towel and place in a glass or steel pie dish (do not use aluminum).
3. Dampen another paper towel and lay on the corn.
4. Insert pan in large, loose plastic bag and place somewhere warm (70 -80 ).
5. Check often to assure upper towel stays damp.
6. In two-four days corn seed will sprout and all should sprout in double the time the first one does.

What to look for: You may be surprised where and how corn seed sprouts. The first sprout appears on the side of the seed and is called a false root. About a day later the shoot appears (Fig A). If both root and shoot appear you can consider the test complete and determine if you have a sizable percentage of bad seed.

It will take up to another ten days for the true roots to appear around the false root (Fig B). By this time the false root may be ten inches long, and the shoot will be above the soil. If you have corn shoots appear then stop growing, it can be that true roots do not develop. This problem has been found in first year new varieties. Some sees have developed only a false root or only a shoot.

Fig. B
Fig. B

Other Hints: Once you have tested corn seed you will probably ask yourself, “Why not sprout all the seed and plant just the good ones?” The chance of a sprouted seed rotting during a period of bad weather is very small. You could encounter a problem. By the time all the seed sprouts appear the false root of some may be up to two inches long and curled and twisted so the seeds are difficult to separate without damaging the delicate root or shoot. Put the twisted Seeds in a small bucket of water to separate them and when planting, press the soil down a bit less than usual.

Have a bad back? Don’t like bending down to place tender sprouted seeds in the trench? Then don’t! With a string loop, hang the bucket around your neck. Then using a piece of 1-1/2 to 2 inches in diameter tubing about 3-4 feet long, drop the seeds down into the trench.

Using this method you will find that you can plant corn earlier and with better results. Here are some other ways to gain still earlier results: Early tests that led to developing tunnel gardening showed that placing a narrow strip (about 10 inches) of clear plastic over the row, and holding it down with boards or soil, gave the soil warmth and seeds sprouted in about 1/2 normal time. However, the plastic must be removed as soon as sprouts appear.

FigCPlastic The next development was to stand a 2X4 board on the north side of the row to prop the plastic (about 15 inches wide) off the ground. This allows the corn to grow about 4 inches high and birds are no longer its worst enemy. (Figure C)

The ultimate way though, is using the fiberglass tunnel (see QA #2 – Plastic Culture) to get at least part of your corn a foot high, quickly.

Birds in corn? If you don’t use tunnels and young corn shoots disappear, crows or blackbirds may not be the villain. Smaller bird-like sparrows are masters at this. Even mice can take on a row a night. If you don’t tunnel, train your cat to guard the corn!

Prepared by: Ward Briggs, Washington State University Master Gardener.
Slightly revised 5/98 by Dave Pehling, Snohomish County Extension Analyst
. link updates 01/02/13