Faster, Better, More Even Germination

While no one seeding system can always result in ideal germination rates, there are some ways to promote smooth and even germination. Research agronomist Ross McKenzie with Alberta Agriculture Food and Rural Development at Lethbridge, and Canola Council agronomist Doug Moisey at Fort Macleod, Alberta offer expert advice

Fertility Boost

A fertilizer boost may be just what you need next season to jump-start your crop.

Adding starter phosphate to the seedrow will boost crop emergence and vigor. Plants must receive phosphate in the early growth stages to build strong, internal structures. "Wheat and barley, for example, take up 70 percent of the season's phosphorous supply in the first 40 days after emergence," Ross McKenzie points out.

Soil-applied granular phosphate dissolves quickly for immediate access by emerging roots. Early direct seeding into a cool seedbed definitely requires the "pop-up" fertilizer application.

"Regardless of the soil profile or the crop, if the ground is at all cool, the seed will benefit from 15 pounds of actual phosphate in the seedrow," McKenzie says.

Barley, wheat and canola are all highly responsive to 15 pounds of soil-applied phosphate. Pulse crops also benefit but will show a less dramatic response. "The upper limit for immediate benefits from soil-applied phosphate seems to be at about 30 pounds," McKenzie says.

Accurate Temperature Reading

Use a thermometer to get accurate soil temperature readings. "Put the probe down to seeding depth after breakfast and before supper," says Doug Moisey, "and take the average as that day's soil temperature. Do that a few days in a row."

When the average breaks 5 degrees C (41 degrees F), it's early but not too early to seed. "When the average hits +10 C (50 degree F), you should be too busy seeding to bother taking the soil temperature."

Kernel Weights

Even germination and seedling viability start at seeding by determining the correct kernel weight.

To achieve a precise number, count and weigh 1,000 kernels of the seed you plan to sow, then convert the seeds per square foot to pounds per acre. A calculator is available on the Alberta Agriculture site at www.agric.gov.ab.ca as well as several other sites.

"Do not assume you know the 1,000 kernel weight," says Moisey. "Kernel weight is totally variable, by variety and by seed lot. If the seed is plumper this year and you calibrate for last year's rate, you will end up with fewer seeds per square foot."

Alberta Agriculture researchers recently performed 1,000 kernel counts on seed from six varieties of malting barley. To achieve a target rate of 25 seeds per square foot on selected seed lots, they needed only 102 pounds of CDC Sisler, a 6-row barley, but went to 127 pounds of CDC Stratus, a 2-row barley, to hit the target.

Kernel Size

Thin seed isn't glamorous. Choose the plumpest kernels you can find.

If in doubt, run a bag of certified seed through a separator. Plant equal numbers of thin and plump kernels at depths of 1, 2 and 3 inches, water well and watch what happens.

"A higher percentage of plump kernels will emerge," says Moisey. "Usually they'll also be more vigorous. The deeper you seed the kernels, the lower the percentage that will emerge."

Fertility

Seed grown with less-than-adequate fertility can look plump and healthy, but good looks have deceived more than one grower.

"Researchers have taken seeds from fertility trials, performed germination tests, then planted them in new trials under equal conditions," says MacKenzie. "The results were interesting. Initially all the seed looked identical, the germination test results were good, but inside, the seeds weren't equal."

The point: Seed taken from adequately fertilized trials showed better emergence and more vigor than seed taken from trials with a fertility deficiency.

If in doubt, ask a lab to perform a seedling vigor test. It takes about 6 weeks so plan ahead.

Many growers worry about seeding at too high a rate. The theory is that too many plants per square foot will use up all the moisture before the seed is ready to fill.

"A slightly higher-than-recommended plant population even on dry land is probably the best long-term approach," says Moisey.

Deeper Isn't Better

Within reason, the producer's best bet is to seed as shallow as possible. Warm seed in shallower soil germinates faster, emerges more quickly, and the shoot has more vigor.

"Seeding too deep is a big issue," says Moisey, "and it's often related to management rather than calibration of the seeding equipment."

He says that typically in conventional tillage the producer sets up a cultivator on the lowlands in the fall, then works the whole field with big horsepower.

"The following spring, it's mellow. On the hilltops, the soil has been worked to 7 inches deep, and in the dips, often less than 2 inches has been worked," he says. "As the press wheels close the seedrows, the seed ends up displaced. On hilltops, canola can get buried 5 inches deep."

Improve Seed and Soil Contact

Be very sure that your seed is placed on a firm bed. "Seed needs firm soil contact to soak up moisture," says Moisey. "It also needs a little breathing space so it can send the shoot to the surface then into the light—without dying in the process."

Ideal depth for canola seed is 1/2 to 1 inch below the press wheel furrow. If the soil isn't firm enough at that depth, the seed can very easily get stranded in dry soil.

"Walk on the field a little bit and check your footprints," Moisey advises. "If the heel print from your boot is less than 1 inch deep, the seedbed is firm enough.

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