Buy enough seed to meet population targets

December 11, 2013 - Issue 29

Canola stems

The ideal canola stand will have 7-10 plants per square foot. Canola needs a minimum of 4-5 plants per square foot, on average, to reach its yield potential. A few extra plants improves the chance of hitting yield targets, and allows for some plant loss to insects and disease. Canola with plant populations below 4-5 per square foot can still yield fairly well under good growing conditions and with good pest management, but it will not likely reach its yield potential.

The seeding tool used to put in the crop does not change this fact.

A seeding rate calculator shows that about 5 plants per square foot square should result from 5 lb./ac. of seed with a 5g thousand seed weight and 50% emergence. Here’s a calculator to try, although it’s not designed specifically for canola. Most growers are likely dealing with plant stands lower than ideal.

Things to keep in mind:

—High success rates for germination and emergence in the spring of 2013 is not something to count on each year. Choose a seeding rate that provides some cushion. Seed emergence rate is usually 50-60%.
—Wide row spacing that results in higher seed populations per row is known to increase seed mortality. Given this fact, cutting seeding rates with wide rows may result in critically low plant populations.
—Wide rows also mean the seed-placed fertilizer per row will be more concentrated. This could also increase seedling mortality.
—Wide rows mean later canopy closure and reduced weed competition from canola plants. This may increase the need for a second herbicide application that may not otherwise be necessary with narrow rows.

Drills article in Canola Digest. For more on the best canola seeding tools, keep an eye out for the January Canola Digest, which will arrive in mailboxes early January and be posted here.

Canola Watch