|Soil Temp||65° F+|
|Area to Sow||5’x5′ area|
|Days to Germ.||3-10+|
|Days to Maturity||80+|
|Best Planting Method||Direct or transplant|
|Thin to||Final spacing|
|Final Spacing||≥6″ apart|
|Approx. Seed Count||39|
Planting by Zones
- Corn is a warm season crop that should be grown when soils have reached a minimum temperature of 65°F. This occurs in mid-May in Zones 9 and 10. It will not germinate well in cold soils.
Planting Corn Seeds
- Corn seed is very easy to direct sow. For Zones 9 and 10, sow seeds in deeply irrigated soils to guarantee even and quick germination. Plant seeds every 3″, thinning later to 6″ apart.
- Fertilize regularly with an organic liquid fertilizer once the seedlings have germinated and are about 4″ tall.
- If transplanting out, plant in the garden when it is 6-7″ tall. Space at least 6″ apart. Plant in full sun.
Succession Planting Corn
- Plant every 10-days for a continuous crop to harvest.
- For healthy kernel development, you must ensure good pollination. Pollination happens when pollen from the tassels falls onto the silks. To ensure this, corn must be planted in blocks, and you must plant at least 10 plants to get a good yield. Plants can be grown very close together if you are planting in a small space.
- Corn requires adequate moisture and moderately fertile soil to produce a healthy crop. Side dress with a granular organic fertilizer if you believe your soil has low fertility.
Growing Corn in Containers
- Do not grow in a container unless you can fit a minimum of ten plants in the size of the container being used.
- Corn is harvested differently depending on the type you grow.
Sweet Corn is harvested when the peak sugar has condensed in each kernel—ears will feel firm and full. Other signs of maturity are dry silks and ears that are tilted from the stem. You can peel back the silk and squeeze a kernel. If the liquid that comes out is milky, it’s ready! Keep in mind the quality of sweet corn declines if you let it stay on the stalk too long. Sugar contents turn to starch, making the corn less appealing to eat fresh. If this happens to you, simply use the corn in cooking applications like corn chowder, corn cakes, or other recipes.
Popcorn/Mill Corn and Dent Corn are left to mature on the cob. As they mature, the silks will dry out. These types can be stored dry until needed. Popcorn can be popped by placing the whole cob (husked) in the microwave in a brown paper bag.
Southern California Pro-tips
- In areas of Zones 9 and 10, corn can be succession planted several times for a harvest that can be enjoyed all year long!
- Aphids and ants are the most common corn issues in Southern California. Refer to UC IPM.