Courses / Preseason Preparation

Course Content

Prepare the Hatchery
Soak New Equipment Service Mechanical Equipment Prepare Your Nutrient Solution
Prepare Your Seed Spools
Define Your Production Target Make Your Spools
Choose a Seed String Wrap Your Spools
Resources & Tools
Provasoli's Enriched Solution (PES) Volume Calculator for Kelp Nurseries
Download file
Soaking and Leaching Spools for Kelp Nursery Production: Step-by-Step Guide
Download file
Lesson 2 Prepare Your Seed Spools

Back to: Preseason Preparation

Choose a Seed String

There is no standard seed string in the kelp farming industry, and many different types of string or twine may work. When selecting your brand and material of seed string, here are some key considerations to look out for. 

GreenWave has historically tested 3 kinds of seed string:

  1. Korean seed string (1mm)

  2. Japanese Cremona (2mm)

  3. American Holdfast tufting twine (1mm)

Seed String Checklist

  • Good surface area for spore settlement

  • A thickness that will optimize the linear feet on each spool 

  • Durable enough to hold up on the farm

The first type of string we’ve used is a Korean seed string. This is a very expensive 1mm string that is found only at special shops in South Korea which makes it very difficult to obtain. 

The second type of seed string we’ve tested is Japanese Cremona, a somewhat expensive 2mm thick string. Spores settled very well on this string, but the thicker string cuts the number of linear feet on each spool in half when compared to the other types. Farmers also noticed that the thick string made it difficult to lay into the weave of the growline during outplanting.

Finally, we have tested American holdfast, a 1mm thick nylon tufting twine that is normally used in upholstery. It’s easily accessible and much less expensive than the alternatives. We have found that it works just as well as the other strings and is now our go-to option.

Top string: Nylon Holdfast ; Middle string: Korean seed string ; Bottom string: Japanese cremona
Left: Nylon holdfast ; Middle: Japanese cremona ; Right: Korean seed string
Industry Tip

Regardless of the seedstring you use, it is important to find out as much as you can about the manufacturing process and what chemicals the string may have come in contact with. As a precaution, soak all seedstring after it is wound onto seed spools but before seeding to allow any excess chemicals to leach out. Soaking entire spools of fresh string before they are wrapped on seed spools is not sufficient because the inner wraps will not be exposed to water.