|Item Form ||Seeds |
|Additional Characteristics ||Edible |
|Light Requirements ||Full Sun |
|Soil Tolerance ||Normal, loamy |
|Uses ||Outdoor |
Corn is one of the most versatile and best-loved veggies you can grow. It's been cultivated for thousands of years, increasing in popularity over time, as its attributes have become more and more obvious. Not only is it delicious in a wide variety of dishes as well as fresh from the stalk, but its uses go well beyond the culinary world. From Corn-on-the-cob and popcorn to syrups and cereals and an abundance of other products (edible and not!), this tasty vegetable is truly remarkable!
Choosing a Variety
When choosing what type of Corn to grow, you'll be able to pick from white, yellow, and bicolor varieties as well as consider a number of other traits that affect taste and tenderness. Here's a list of different hybrid varieties and their main characteristics:
Regular Sweet Hybrids -- Traditional, old-fashioned Corn flavor, delicious without an emphasis on sweetness. High yielding.
Sugar Enhanced Varieties -- Sweeter than regular strains, and with a sweetness that lasts longer after the Corn has been picked. A creamy, tender texture and no planting isolation needed from other Sweet Corn.
Super Sweet Varieties -- Bred for twice the sweetness of regular Corn. Will hold their tenderness and sweetness up to two weeks. They must be planted in totally warm soil and kept isolated from other types by 200 feet or 14 days planting time.
New Triple Sweet Varieties -- Wonderfully sweet, but they were bred to add more original Corn taste to the sweetness, improve crunchy texture, and hold their flavor and sweetness even longer. Requires no isolation from other Sweet Corns.
When to Start
Corn is best sown outdoors in situ after all danger of frost has past in spring. Sow in warm soil -- optimum temperature is at least 60 degrees F. Sweet Corn can be started indoors 2 weeks before the last frost at a temperature of 70 to 75 degrees F, but direct sowing is recommended.
How to Start
If you want a continuous crop, sow every two weeks until early spring. Sow at a depth of 4 times the size of the seed in rows that are 24 to 36 inches apart. Plant in full sun in a rich, moist, well-drained soil. Once the seedlings appear, thin them to 3 to 12 inches apart. If you have started them inside and are transplanting them, do so when they have at least two sets of true leaves and allow them the same amount of space as previously mentioned. Expect germination in 7 to 10 days.
Cross-pollination can occur between different varieties of Corn, affecting taste, color, and other qualities. To prevent this, isolate each type by at least 700 feet, or allow at least 14 days between times of maturity.
Do not plant sooner than 10 days to 2 weeks after the date of the last killing frost. If you plant too early, your seedlings may die or their growth can be delayed.
Since Corn is wind pollinated, it's better to plant 4 or more short, side-by-side rows than 1 or 2 long rows. This will help pollination and ear development.
- Side dress your Corn plants with a high-nitrogen fertilizer.
- Harvest your Sweet Corn once the silks have dried -- this will be approximately 3 weeks after silking.
- Harvesting: break the stem of the ear (shank) close to the ear. Avoid breaking the main stock or tearing the stem from the stalk. Just hold the ear near the base and bend it down sharply. You can also bend it to the side.
- You can expect at least one ear (sometimes more) from each stalk.
- In order to maintain the sugar content you will want to refrigerate your Sweet Corn right away.
Pests and Problems to Watch For
- Corn borer -- This moth's larvae feeds on all above-ground tissues of the plant. The cavities they produce interfere with the translocation of water and nutrients, thus reducing the strength of both the stalk and the ear shank. Some methods of control include using a pest-resistant variety, destroying infected stalks at the end of the season, and harvesting early before the moths have a chance to lay eggs.
- Corn earworm -- These caterpillars feed on the tips of the ears of Corn, devouring the kernels and sometimes even destroying the silks before pollination has completed. This results in deformed ears that are susceptible to disease and mold. They can be controlled with Bt, a natural bacteria that produces toxic proteins that kill certain insects. You can also till in fall and spring to expose pupae to wind, weather, and predators, release beneficial insects such as trichogramma wasps, lacewings, minute pirate bugs, and damsel bugs, or use botanical insecticides (always read instructions and cautions before use).
- Smut -- Corn smut is caused by a fungus, and it can be removed by hand and buried or burned. Since the spores can get into your Corn through injured parts of the plant, try to avoid injury of roots, stalks, and leaves during cultivation. Also, plant disease-resistant varieties when possible, and at the end of the season, plow diseased stalks to bury any surviving spores.
- Stewart's disease (bacterial wilt) -- This disease is caused by a bacteria that's transmitted by several insects, namely the flea beetle, which will over winter and spread the disease once it starts feeding on the new year's crop. To control it, plant disease-resistant plants whenever possible, eliminate or discourage the presence of flea beetles, and don't use seeds that were produced in a field contaminated with Stewart's wilt.
- Flea beetle - Flea beetles, so named for their tendency to jump when disturbed, love Corn. They produce a characteristic injury to leaves known as "shot-holing." Young plants and seedlings are particularly susceptible to this damage. You can use Sevin® Dust or organic Neem oil to control them.
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Superior Germination Through Superior Science
Park Seed offers some of the highest-quality vegetable and flower seeds available in the industry, and there are a number of reasons for this.
First of all, we have humidity- and temperature-controlled storage, and we never treat any of our seeds with chemicals or pesticides. Nor do we ever sell GMO's (genetically modified seeds), so you always know the products you're buying from us are natural as well as safe for you and the environment.
Superior Standards - University Inspected
To make sure we are providing the best seed product possible and that our customers will get the highest number of seedlings from every packet, we conduct our own germination testing and have quality-control measures in every stage of our seed-handling operation. We hold ourselves to standards that are at or above federal and state standards, including testing specific crops more frequently than recommended by federal guidelines. And in order to maintain our organic certification, we welcome Clemson University to inspect us annually to make sure our organic seeds, which are stored and processed separately, are being handled properly.
Hand Packed By Experienced Technicians
Park Seed has been handling and packing vegetable and flower seeds for 145 years, a history that has given us a great understanding of how each variety should be cared for and maintained throughout every step of theprocess, from collection to shipping.
When packing our seeds, the majority are actually done by hand (with extreme care!), and we often over-pack them, so you're receiving more than the stated quantity.
The Park Seed Gold Standard
And many of our seeds are packed in our exclusive Fresh-Pak gold foil packets, which are lined to keep moisture out, so the seeds stay fresher for longer. We carefully pack very tiny or fragile seeds in crush-proof vials to ensure safe delivery to your home. Some of the small seeds are also offered as "pellets" (have a clay coating) to make sowing and growing easier.
When it comes to the kinds of seeds we offer, we are constantly seeking something new and provide many unique and hard-to-find varieties from all around the world. Our on-staff horticulturists are ready and available to share their expertise to help you with the success of these seeds, so you can grow a beautiful and productive garden!
Does Park sell GMO's or treated seeds?
It is important for our customers to know that Park Seed does not sell GMO or treated seed. We do buy a small amount of traditional hybrid seed from Seminis, a division of Monsanto Co., but that is all we purchase from them.
What are the differences between organic, heirloom, and hybrid seed?
Basically, organic seeds are seeds that are produced without the use and exposure to artificial/chemical fertilizers, insecticides, fungicides, herbicides, and other chemicals. They have to be grown, harvested, stored, and handled under very strict organic rules and procedures. All of our organic seeds are USDA 100% certified organic through Clemson University and the certificate has to be renewed yearly.
Heirloom Seeds are open-pollinated -- they are not hybrids. You can gather and save heirloom seed from year to year and they will grow true to type every year, so they can be passed down through generations. To be considered an heirloom, a variety would have to be at least from the 1940's and 3 generations old (many varieties are much older -- some 100 years or more!).
Hybrid seed are the product of cross-pollination between 2 different parent plants, resulting in a new plant/seed that is different from the parents. Unlike Heirloom seed, hybrid seed need to be re-purchased new every year (and not saved). They usually will not grow true to type if you save them, but will revert to one of the parents they were crossed with and most likely look/taste different in some way.
What are pelleted seeds? Why do you use them? How do I handle/sow them?
Extremely small seed such as Petunias and Pentas are shipped as pelleted seed to make them easier to handle and sow. Pelleted seed are coated, usually with clay, to make them larger in size. After sowing, the coating will dissolve when wet and the seed will germinate. Pelleted seeds are shipped in vials placed inside seed packets, which protects them from being crushed. When sowing, be certain to use thoroughly moistened soil, to be sure that the clay coating absorbs enough moisture to dissolve. For sowing pelleted Petunia seeds, place the seeds directly on the soil surface and do not cover with soil, as light aids in the germination.
What is ideal temperature to germinate most seeds?
The ideal temperature to germinate most seeds is approximately 70 degrees F; give or take 1-2 degrees either way. This would be a good germination temperature for most flower and vegetable seeds and would be the most practical and feasible temperatures achieved for gardeners starting seeds in the home. You will notice for some seeds that it is recommended to use alternating day (warmer), night (cooler), temperatures, which is fine if one can provide such conditions. But most people are unable to provide those temperatures in a home setting, so just use the overall 70 degree F recommendation and the seeds should germinate well.
How long should grow lights be kept on per day and how close to the plants should the light be kept?
For germination and seedling/plant growth, you want to simulate the natural day-night cycles, and as a general rule, grow lights should be on 8-12 hours per day and off at night. You can vary this timing, as some seeds such as tomato, pepper, petunia, impatiens, and others, benefit from 14-17 hours of light per day (and the remainder of the 24 hour period in darkness). The most common grow lights used are fluorescent; using cool white, warm white, and wide-spectrum fluorescent tubes. These lights work well for germination and for growing plants up to a transplantable size. Fluorescent lights should be kept close though, 3-6 inches above the soil or the growing plants, adjusting the height as the plants grow.
How long will seeds keep in storage?
Park Seed stores seed in a special temperature- and humidity-controlled storage facility, which keeps seeds in excellent condition. Our seeds should be good for at least 1-2 years on average. Seed viability and storage time will vary depending on the seed item; some will keep a shorter time and some will keep longer. Seeds should be stored in a cool, dark, dry place. A basement will do (if not too humid), or a cool, dark room or closet. We recommend the best way to extend seed storage life is to store them in something air tight, such as a plastic zipper storage bag or canning jar, and place it in the refrigerator. This will extend the life of seeds for many years.
What is the best way to store seeds over a longer time period?
We recommend the best way to extend seed storage life is to store seeds in something air tight, such as a plastic zipper storage bag or canning jar, and place it in the refrigerator. This will extend the life of seeds for many years.
What depth should I sow various seeds?
When sowing seed outdoors, we recommend a maximum planting depth of 4X the width of the seed. When sowing seed indoors, the planting depth can be less, depending on the seed being sown, so it is always best to check specific directions. Here are some general guidelines concerning planting depth in relation to seed size: Tiny, dust-like seeds need to be sown on the surface of the growing medium or soil, uncovered, as they need light to germinate. The planting depth for small seed can be anywhere from barely covering, to 1/8-inch deep, to possibly 1/4-inch deep, depending on the recommendation. Medium seed should be planted at 1/4- to 1/2-inch deep, depending on the recommendation. Larger seeds can be planted 1-inch or deeper, depending on the recommendation.