pointer80
Senior Member
Posts: 233
Joined: Sun Mar 24, 2013 1:50 pm
Location: northern Michigan

any ideas what causes this on corn

My corn seemed to do ok this year and have great taste but the ears didn't get real large and didn't fill in all the way. Any ideas why they didn't fill in all the way? Thanks all.
Attachments
IMG_3227.JPG
IMG_3226.JPG
IMG_3228.JPG

imafan26
Mod
Posts: 13986
Joined: Tue Jan 01, 2013 8:32 am
Location: Hawaii, zone 12a 587 ft elev.

Incomplete pollination. Not all of the silks on the ear got pollinated. Usually you have to plant corn in a block and have a minimum 4x4 block. The first ear usually gets enough pollen but second and third ears don't unless you plant a second set of the same corn about a week later around the perimeter just for pollination of secondary ears. Corn on the outside of the block will not be as well pollinated as those in the middle. When you don't have a lot of corn plants you can bag the tassels and collect the pollen and hand pollinate the ears. Corn is wind pollinated and most of the pollen drops down. James says be mindful not to plant the corn stalks too close otherwise they get in the way of the pollen reaching the ears. 10-12 inches apart in a block .

xtron
Cool Member
Posts: 96
Joined: Sun Jun 25, 2017 5:20 pm
Location: christiansburg virginia

looks to me like not enough water at a critical time. this could be from drought/lack of rain, or, as in my case, over planting/crowding.
corn needs a bunch of water from the first sign of tasseling, to the time the kernals are filled. don't know how much per week, but I use a moisture meter and try to keep the level towards the high end of the normal range. some times this means irrigating every other day, if it doesn't rain. this year, I over crowded and even this much water wasn't enough, I had a lot of ears that looked just like your pics. another plot, planted with half the amount of corn, was just fine, really good, full ears of golden bantum.
the other cause I know of would be poor pollination. if you plant a single row, or only two rows, you will not get optimum pollination, but you would see your simptoms randomly spaced over most of the cobs.

imafan26
Mod
Posts: 13986
Joined: Tue Jan 01, 2013 8:32 am
Location: Hawaii, zone 12a 587 ft elev.

Smaller ears could be because it is a different variety, but certainly if the corn is not grown under optimum conditions, the ears will be affected
Corn is a heavy feeder so it need to have a couple of shots of nitrogen
Corn needs to have enough water or it will age faster the corn plant and ears will be shorter and ears will have small kernels.
I do see some unfilled kernels but the rest of the corn on the ear looks o.k.

Taiji
Greener Thumb
Posts: 921
Joined: Fri Oct 05, 2012 3:19 am
Location: Gardening in western U.P. of MI. 46+ N. lat. elev 1540. zone 3; state bird: mosquito

Sometimes if I get that phenomenon it occurs on my secondary ears. (I usually get 2 ears per stalk) The secondary ear is the one lowest on the stalk. Since all the ears get the same pollination, I'm thinking it's a nutritional/water thing. The main ears get most of the nutrients and water so maybe not that much left for the secondary ears? (maybe the plant just makes this decision on its own!) My main ears are always fully formed. I give my corn about 2 shots of extra nitrogen during the season as was mentioned, and plenty of water during the crucial time as was mentioned.

imafan26
Mod
Posts: 13986
Joined: Tue Jan 01, 2013 8:32 am
Location: Hawaii, zone 12a 587 ft elev.

The tassels appear before the corn ears are ready to accept the pollen. If it is especially windy you will lose pollen faster and it will drift farther away. I can get up to 3 ears on a stalk. The first is usually filled but the second and third come out later, by then, most of the pollen has already dropped the second ear might be partially filled but the third ear is usually very short and corn kernels are larger but very spotty on the ear. Corn is ready to pick about 10 days after the tassels appear. Late ears just don't have as much time to pick up pollen unless it is hand pollinated. It is not a nutritional or water thing, it is just timing when the pollen is ready and when the ears appear. If you have multiple ears and not a very big patch of corn, you will get a higher yield by bagging the tassels and hand pollinating. If you have the space, you could plant alternate rows 5-7 days later to have tassels and pollen for the secondary ears. The pollination window for corn is very short. That is why you can plant different varieties 2 weeks apart to keep them from accidentally crossing.

User avatar
applestar
Mod
Posts: 30540
Joined: Thu May 01, 2008 7:21 pm
Location: Zone 6, NJ (3/M)4/E ~ 10/M(11/B)

Another problem that could happen is aphids and/or Japanese beetles damage the silks and later kernels (topmost) don't get the chance to develop.

pointer80
Senior Member
Posts: 233
Joined: Sun Mar 24, 2013 1:50 pm
Location: northern Michigan

thanks everyone

User avatar
jal_ut
Super Green Thumb
Posts: 7447
Joined: Sun Jan 18, 2009 10:20 pm
Location: Northern Utah Zone 5

Pretty common to see the ears with the end not filled out. Others have given you some good reasons why. I am going to suggest: Don't worry about It. Steam those ears and enjoy!



Return to “Vegetable Gardening Forum”