Seeds turn into plants, plants make grain and grain in the bin turns into money. The rate you seed your crop establishes your overall plant population in the field. Plant population in the field establishes the tone for your yield in the subsequent harvest. Combined with your seed’s thousand kernel weight (TKW) and expected seedling survival rate, your seeding rate can be determined through a simple equation.

Thousand kernel weight is simply how much 1,000 seeds weigh. You can determine this by counting and weighing 1,000 seeds of any crop you are seeding. Estimates of your variety TKW are also provided in the table below for your crop type. The expected seedling survival rates can be determined using guidelines for average growing conditions. For cereals, expected seedling survival is 80 to 90 per cent. The expected seedling survival rate for canola is 40 to 60 per cent. Pulses have an expected seedling survival rate of 80 to 95 per cent. These rates may need to be adjusted depending on expected soil moisture, weather, seed quality, amount of seed placed fertilizer, weed pressure, and seeding date. To have exact measurements of both your TKW and expected seedling survival rates, get your seed tested by an accredited lab. Not only will you get these two measurements, but you’ll also be able to get numerous other measurements that are helpful when seeding your crop.

To calculate your seeding rate, multiply your target plant population (per square meter) by your TKW. Divide this by your expected seedling survival rate. This will give your seeding rate in kg/ha. To convert to lbs/acre, multiply by 0.89.

To gauge when to start seeding, take readings of your soil temperature at the appropriate seeding depth in the morning and the afternoon at various spots in the field. Use locations in the field that represent your field overall. The average of these readings is your field soil temperature. The recommended minimum average soil temperature (at seeding depth) is required for the seeds to germinate and is listed in the table below. However, after germination your crop is exposed to the environment so be sure to consider risk of frost.

A well-established crop is the first milestone to having a successful cropping season. Calculating your seeding rate and seeding at the right soil temperature is the first step to a well-established crop. If considering applying a seed treatment to your crop before seeding, be sure to check out the Guide to Crop Protection. Contact your local crops extension specialist for any additional information on seeding rates, seeding depth, or soil temperature.  

Crop Target Plant Population - per square meter (Thousand Kernel Weight - in grams)

Wheat - Hard Red Spring 250 (31-38)

Wheat - CPS 250  (39-50)

Durum 210-250   (41-45)

Wheat - SWS 210-250   (34-36)

Wheat - Winter 250   (30-36)

Barley - 2 row210-250   (34-36)

Barley - 6 row210-250  (30-45)

Oat      350      (30-45)

Triticale - Spring   310  (42-48)

Triticale - Winter  250   (43-46)

Fall Rye 250   (30-35)

Grain Corn      7     (200-270)

Canary Seed   500-570   (7-8.5)

Canola - Brassica rapa   80-100   (2-3)

Canola - Brassica napus  80-100  (2.5-7.5)

Flax    300-400    (5-6.5)

Camelina    210    (1-1.3)

Mustard - Yellow   70-120   (5.5-6.5)

Mustard - Brown/Oriental  70-120  (2-3)

Soybean       44-57       (N/A)

Hemp - Grain   100-125    (12-18)

Pea           85        (125-300)

Red Lentils  130    (35-40)

Large Green Lentils   130-190   (64-75)

Chickpea   44    (220-450)

Faba Bean   45   (350-425)

Dry Bean   40   (160-900)


Crop    Recommended Min Avge Soil Temperature at Seeding Depth - Celsius   (Recommended Seeding Depth in cm/inches)

Peas                 5      ( 3.8 cm / 1.2-3.2 in )

Lentils               5       (2.5-7.5 cm 1-3 in)

Chickpeas - Kabuli    10     (3.5-6 cm  1.5-2.5 in)

Chickpeas - Desi    7          (3.5-6 cm  1.5-2.5in)

Faba Beans           3-5       (5.1-7.6 cm    2-3 in) 

Dry Beans           12           (5-6 cm  2-2.5 in) 

Soybeans           10         (1.9-3.8 cm  .75-1.5 in) 

Wheat                4           (4.0-6.0 cm   1.5-2.5 in)

Barley                3-5        (3.8-4.5 cm 1.5-1.75 in) 

Oats                  5            (2.5-5.0 cm   1.0-2.0 in) 

Canola - Brassica napus      5           (1.5-2.5 cm    0.5-1.0 in) 

Mustard           5               (1.5-2.5 cm    .5-1.0 in) 

Flax                 5                (2.5-4.0 cm    1.0-1.5 in) 

Canaryseed     5                   (<6 cm  <2.5 in)