I'm not a pro but from what you just said, the ear was not fully filled maybe because it was picked too early? Harvesting corn at the right time is truly a skill that comes with a lot of trial and errors. Hope you have better luck next time.

three rows of 10 plants

3 rows is a narrow band and can easily result in poorly formed ears. 5 rows of 6 would get you better pollination. Square is always better than a long rectangle for pollination.

Small ears is a nutrient problem unless it was a small ear variety. You don't give the variety name and you don't mention what you used to feed or at what stages of development you fed. Corn needs very high nitrogen feeding and only a few common fertilizers gardeners buy are high enough in nitrogen. And application time is crucial. How tall were the plants, what color were the leaves (how dark green)?

"Gumy" like ceth said is usually a harvested too late problem.

Dave

As Dave stated corn needs lots of nitrogen and I'll add lots of water. Small ears are usually due to those factors or from being planted too thickly.

In CA and TX corn needs an inch of water every two days unless the soil is exceptional. This rate would apply after it reaches 2-3ft tall. Less before then.

I'm in Zone 9 too. Not a pro though. My corns are all harvested and eaten by 4th of July. I planted mine on March 15th. When did you plant yours? Why are you harvesting so late in the season?

"Small, gummy and not fully formed" to me sounds like poorly pollinated ears that stayed on the plants too long. I grow small plantings, too, and when they are in tassel I make a habit of thumping the stalks in the late morning to release fresh pollen. Some of the late ears have no fill at the tip end, but most of the ears are perfect. Variety makes a difference, too. In my climate Luscious fills out really well even in bad weather, but you may find something better in your climate.

Thanks all. I planted Silver Queen and Golden Jubilee in mid-April, staggered dates. Likely not enough nitrogen, but water ample. My planting configuration was the best I could do, I have read square is better than rectangular. I also attempted to grow the three sisters. That too didn't turn out so well. Back to the old drawing board for next year! BTW avocado 1 where are you in zone 9? I'm in Walnut Creek.

Thanks all. I planted Silver Queen and Golden Jubilee in mid-April, staggered dates. Likely not enough nitrogen, but water ample. My planting configuration was the best I could do, I have read square is better than rectangular. I also attempted to grow the three sisters. That too didn't turn out so well. Back to the old drawing board for next year! BTW avocado 1 where are you in zone 9? I'm in Walnut Creek.

I live near Diamond Bar in Southern California. The weather has been cooler than usual, until now. It's really hot; hitting 99 degrees today. As long as I can remember, it is always hot around Labor Day.