Sustainable Sweet Corn Production?

Sustainable Sweet Corn Production?

A few facts Very! Crop Per capita consumption of 30 lbs. 3 rd highest consumed vegie behind potatoes and tomatoes. 73% for Processing 23% for Fresh Market Only 30% of acreage is for Fresh but 60% of total farm value.

Classification, Origin, History Zea mays member of the grass family Genetically a mutant of field corn Recessive gene sugary (su) increases sugar accumulation in the kernel. One of few vegetables native to New World, probably Central America Found corn cobs in caves dating back 7,000 years.

Plant Growth and Development Monoecious annual Both sexes on same plant. Unique: single dominant stem headed by male inflorescence (arrangement of flowers on the axis) Male = Tassel Female = Ear Cob = receptacle holding the ovaries (future kernels) Kernels are fruitlets storing sugar and starch Each kernel develops from individual flower Silk = stigmas & styles for each fruitlet or kernel Male Flowers open shed pollen by air currents =/- 9 days.

Incomplete Tipfill Caused by Improper pollination which is caused by Drying or killing of pollen grains or silks by high temperatures Or pollen not shedding in cold temperatures.

The Ear After pollination sugars move into ear from other plant parts First ear begins at top side shoot of a group of side shoots in the middle of the plant causes a depressive effect on any other potentially developing ears. Kernels increase in size 4 stages: Pre-milk, milk, early dough, and dough.

Subsoil entire farm early spring. Breaks up hard pan. Doesn t turn soil Apply heifer manure at rate of 20 tons per acre & rotovate once. Composting 24-40 parts C:1 part N. Dairy Manure 17:1 (low bedding). Ours is high bedding. Not going to tie up and not going to leach No Fertilizer Broadcast. Soil Preparation

Ready to Seed? Did you spend your winter planning? Or playing? Consistent, daily, available corn is difficult planning task. Weather Get on field? Degree days/temperature # of varieties Number of Seedings

2006 SWEET CORN Days Location # of Row Total # # Lbs. Number Germ Seed Plate and Spacing Actual 2004 linear feet dog hill corner of upper field Harv. Bed width Rows Length Feet of seed of seeds percent Type Actual Lbs sowed & plate #s 1. Row Cover needed required needed per Lb. Trinity Row Cover 0 32 10 375 3,750 3.36 1,912 98% LF B6, B90 Trinity Uncovered 4 32 10 375 3,750 3.36 1,912 98% LF B6, B90 Totals 20 7,500 Total Width/beds 63 10 beds 0.54 acres 2. 5/4-=upper field Trinity 4 32 10 375 3,750 3.36 1,912 98% LF B6, B90 Mystique 9 25 8 375 3,000 1.86 2,772 94% LR B3, B25; C13D7 Totals 18 6,750 5.22 Total Width/beds 57 9 beds 0.49 acres Rows Row Total Lbs to 3. 5/14 = upper field needed Length Feet Sow Trinity 10 25 8 375 3,000 2.69 1,912 98% LF B6, B90 Mystique 15 25 8 375 3,000 1.86 2,772 94% LR B3, B25; C13D7 Delectable 22 32 10 375 3,750 2.05 3,137 97% LR B30, B3; C13D7 Totals 26 9,750 6.59 Total Width/beds 82 13 beds 0.71 acres 203 ft. total width #1-3 2006 Sweet Corn Days Rows Row Total Lbs to 4. 5/21---Hy.10 needed Length Feet Sow Trinity 17 25 8 325 2,600 2.33 1,912 98% LF B6, B90 Mystique 21 25 8 325 2,600 1.61 2,772 94% LR B3, B25; C13D7 Delectable 27 32 10 325 3,250 1.78 3,137 97% LR B30, B3; C13D7 Dancer 37 32 10 325 3,250 1.24 4,484 93% MF B19; C13D7 Totals 36 11,700 6.96 Total Width/beds 114 18 beds 0.85 acres 1,000 ft at 7 " spacing Rows Row Total Lbs to 5. 5/28--Hy. 10 needed Length Feet Sow Trinity 28 13 4 325 1,300 1.17 1,912 98% LF B6, B90 Mystique 32 19 6 325 1,950 1.21 2,772 94% LR B3, B25; C13D7 Delectable 34 25 8 325 2,600 1.42 3,137 97% LR B30, B3; C13D7 Dancer 45 25 8 325 2,600 0.99 4,484 93% MF B19; C13D7 Totals 26 8,450 4.79 Total Width/beds 82 13 beds 0.61 acres 6. 6/4--Hy 9 needed Length Feet Sow Mystique 38 13 4 325 1,300 0.80 2,772 94% LR B3, B25; C13D7 Delectable 40 25 8 325 2,600 1.42 3,137 97% LR B30, B3; C13D7 Dancer 50 25 8 325 2,600 0.99 4,484 93% MF B19; C13D7 Totals 20 6,500 3.22 Total Width/beds 63 10 beds 0.47 acres 260 feet total width Hy10-9 2006 Sweet Corn Perhaps North of Hy 4 Days 1,000 ft at 7 " spacing Or Back Forty Harv Total # Lbs of seed Number of Actual # Actual # Actual Germ Seed Plate and Spacing 1,000 ft at 7 " spacing by Feet proposed Seeds per Lb. Rows Feet Lbs. sowed percent Type 1,714 7. 6/11---Hy9??? 0.57 Delectable 48 2,400 1.31 3,137 12 360 97% LR B30, B3; C13D7 Dancer 54 1,600 2,743 by count 12 340 93% MF B19; C13D7 Totals 4,000 24 Total Width/beds 0.29 acres

Sweet Corn Seeding Schedule 2006 SWEET CORN Days Location # of Row Total # # Lbs. Number Germ Seed Plate and Spacing dog hill corner of upper field Harv. Bed width Rows Length Feet of seed of seeds percent Type 1. Row Cover needed required needed per Lb. Trinity Row Cover 0 32 10 375 3,750 3.36 1,912 98% LF B6, B90 Trinity Uncovered 4 32 10 375 3,750 3.36 1,912 98% LF B6, B90 Totals 20 7,500 Total Width/beds 63 10 beds 0.54 acres 2. 5/4-=upper field Trinity 4 32 10 375 3,750 3.36 1,912 98% LF B6, B90 Mystique 9 25 8 375 3,000 1.86 2,772 94% LR B3, B25; C13D7 Totals 18 6,750 5.22 Total Width/beds 57 9 beds 0.49 acres Rows Row Total Lbs to 3. 5/14 = upper field needed Length Feet Sow Trinity 10 25 8 375 3,000 2.69 1,912 98% LF B6, B90 Mystique 15 25 8 375 3,000 1.86 2,772 94% LR B3, B25; C13D7 Delectable 22 32 10 375 3,750 2.05 3,137 97% LR B30, B3; C13D7 Totals 26 9,750 6.59 Total Width/beds 82 13 beds 0.71 acres

Number of Varieties Mind Boggling And the different types require a plant breeder 1. Normal Sugary (su) 2. Sugary Enhanced (se) & (se+) 3. Synergistic 4. Shrunken (sh2)

Normal Sugary (su) Kernels contain moderate but varying degrees of sugar & they convert to starch rapidly after harvest

Sugary Enhanced (se) and (se+) This gene, when present, modifies the normal sugary (su) gene. The result is much increased tenderness and, to a varying degree, sweetness. The conversion of sugar to starch after harvest is slowed. No isolation from normal (su) corn is necessary. (se) varieties are hybrids b/w (se) & (su) parents. (se+) varieties are hybrids b/w two (se) parents, hence fully sugary enhanced, very tender & sweet.

Synergistic Ears are comprised of 75% se kernels and 25% sh2 kernels. Combine the tenderness of se with the increased sugar content of sh2. Best eating quality = wait for ears to develop fully as sugars develop later than se s. Will taste watery. Grow with other synergistics, se s and su s. Isolate from sh2 s or will be tough & starchy.

Shrunken (sh2) The gene creates greatly heightened sweetness and slow conversion to starch after harvest. Called Super Sweet Must be isolated from other corn types or will result in tough, starchy kernels in both types. What type do we use?

Se+ & Synergistic Now which varieties? Which colors? Yellow? White? Yellow and White or Bicolor? Regional preference = Bicolor By Day s to Harvest?

1) Trinity 68 days Tim s choices mostly synergistic 2) Espresso 69 days +1 days 3) Reflection 72 days +4 days 4) Allure 75 days +7 days 5) Montauk---79 days +11 days!!!! 6) Cameo---80 days + 12 days Let s talk about these...

Estimated Harvest Dates based on proposed seeding dates 2006 SWEET CORN Days dog hill corner of upper field Harv. 1. Row Cover Trinity Row Cover 0 Trinity Uncovered 4 2. 5/4-=upper field Trinity 4 Mystique 9 3. 5/14 = upper field Trinity 10 Mystique 15 Delectable 22 4. 5/21---Hy.10 Trinity 17 Mystique 21 Delectable 27 Dancer 37 5. 5/28--Hy. 10 Trinity 28 Mystique 32 Delectable 34 Dancer 45 6. 6/4--Hy 9 Mystique 38 Delectable 40 Dancer 50

Our objective? Consistent Daily Corn Temperature Issues Sweet Corn is warm-season crop Requires 65-110 days to mature depending upon variety. Prefers 70F-86F. Shoot and Leaves easily damaged by frost but the plant may survive the injury since the growing point remains below ground during a large part of its development and is therefore protected. Germination: depends upon variety. 22 days @ 50F. Probably will rot 12 days @ 59F. 7 days @ 68F. 4 days @ 77F.

Cold, Wet, Soil Temperatures Seed rots? Use treated seed Fungicide Use seed bred for cold soil temps. (Espresso) Grow transplants Use rowcovers Seed through clear plastic

Rowcovers

We overcome cold soil temps. Weather goes from cold to hot to cold (like it usually does in the spring. How do you know when to plant your next crop? 1. Same cultivar every ten days 2. Early, midseason, and late cultivars seeded at the same time 3. System of growing degree days or heat units 4. Or combination of # 2 & 3. We use multiple sowings of different maturing varieties and wait until we see them spike through the soil. Then seed again.

Nutrient Requirements Relatively high nutrient requirement Depending upon soil types 100-160 lb N. Manure 20 tons manure= 100 lb. N.-100 lb. P-200 lb. K. Band 40 lbs. N-P-K @ seeding Sidedress 30 lb. N at 12-20 tall during cultivation

Seeding Simple ground driven seeder probably 50 years old Plates for different size and shape (flats & rounds) seeds Spacing: 7 inches between seeds rows 38 inches apart Plant population = 23,673

No Herbicides but Lots of Cultivation 3x

Problems It s Ok

Clean Cultivated Irrigation critical during tasseling and silking

European Corn Borer: overwinters as a mature lava in corn stalks and stubble. Plowing under refuse in the fall or early spring will help control this pest. Two generations: 1) May-early July 2) Mid July-September Spray pretassel stage (tip emerging from whorls) Spray young ears if pheromone traps indicate flights still occuring. We have never sprayed. Insects

Corn Earworm Read from Manual

Yield 1ear per foot minimum

Harvesting and Postharvest Handling 18-21 days from first silking, harvest ready. Kernels pass from premilk stage to milk stage. Harvest in early milk stage before moving on to early dough stage. Time for harvest depends upon the variety and the temperature. Harvest & cool to 32 F Nobody does it

Soil Tests