Seed Production Planning Part 2 – Calculating Seed Needs

This is the second part of a series on crop planning for seed production. Seed production planning part 1 covered growing small trials to evaluate whether a variety was worth growing to seed on your farm in your climate.

Once you’ve decided the varieties for  this year’s seed production, you need to determine how much seed you would like to harvest.

GROWING SEED FOR MULTIPLE  YEARS

Under good storage conditions most seed will last a number of years. You can grow enough in one year to cover your seed needs for multiple years. This has a few benefits:

  • Growing fewer varieties gives you more space for better isolation distances to avoid cross-pollination.
  • Growing a larger number of plants of on variety provides more plants to observe and you can better select the most fit individuals. Large population also maintain a broader genetic pool that ensures more resilient varieties.
  • Cleaning bigger seed lots is easier than cleaning small seed lots.

For most varieties, I aim to grow enough seed for at least a 3-year supply. (This is not possible for all varieties. I.e. parsnip, leeks and onions lose germination quickly after a year in storage.)

(You can read a previous post about isolation distances and population sizes.)

HOW MUCH SEED DO YOU NEED?

Consider all the ways you sell or use seed, and estimate the needs for each use. This includes

  • Seed you use on-farm. This is calculated from your crop plan – basically the rowfoot you plan to grow multiplied by a seeding rate. (The crop planning for organic vegetable growers handbook covers this.)
  • Seed sold through a seed catalog (in packets or in bulk). This is projected from the previous year’s sales records.
  • Seed sold to other seed companies. This is based on how much seed they need.

Then make a chart to summarize this information. Here are two examples loosely based on our farm.

EXAMPLE 1 – TATSOI SEED NEEDS

Tatsoi is a leafy green from the Brassica rapa species.

At Tourne-Sol farm, we seed a lot of Tatsoi to sell bunching or as part of our salad mixes. We also sell Tatsoi seed as packets to gardeners and in bulk quantities to other farmers.  And our seed company clients purchase regular amounts of our Tatsoi seed.

 Purpose 2012 2013 2014 Total
Farm Use 120g 120g 120g

360 g

Packet Sales 100g(50pkts x 2g) 120g(60pkts x 2g) 140g(70pkts x 2g)

360 g

Bulk Sales 1kg 1kg 1kg

3000 g

For Other Seed Companies 1kg 1kg 1kg

3000 g

TOTAL

6720 g

We’ll need to harvest about 7 kg of Tatsoi seed to meet our projections for the next 3 years.

EXAMPLE 2 – JAUNE FLAMMÉE TOMATO SEED NEEDS

We need significantly less tomato seeds than Tatsoi seeds. Since we transplant tomatoes, our on-farm needs are low and we only sell packets through our seed catalog. Our seed company clients purchase a significant volume but they usually buy enough seed for multiple years at once.

 Purpose 2012 2013 2014 Total
Farm Use 1g 1g 1g

3 g

Packet Sales 5g(50pkts x 0.1g) 6g(60pkts x 0.1g) 7g(70pkts x 0.1g)

18 g

Bulk Sales

0 g

For Other Seed Companies 300g

300 g

TOTAL

321 g

We’ll need to harvest 321 g of Jaune Flammée tomato seed to meet our projections.

——————–

In our next seed production planning installment we’ll figure out how many plants to grow to meet these seed needs.

6 responses to “Seed Production Planning Part 2 – Calculating Seed Needs

  1. This has some useful info on small-scale organic seed production – http://goo.gl/V6NYt

    • Hi Mike,

      Patrick Steiner’s small scale organic seed production is a great reference.

      I’ll actually be referencing in my next post when I talk about seed yields.

      Do you have any other favorite seed books?

      Dan

  2. Pingback: Seed Production Planning Part 3 – How Much To Grow | Going to Seed

  3. Pingback: Seed Production Planning Part 1 – Choosing Crops | Going to Seed

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s