Seed Only Shipping $3.95

Lisa’s New Book The Cut Flower Handbook. Learn More

Homemade Blocking Mix Recipe and Tips

Blocking Mix Recipe:

For 20 cups (makes approximately 500 mini ¾” blocks or 36 of the 2” blocks)

  • 16 cups sifted peat moss or coco fiber
  • 4 cups sifted compost
  • ¼ cup greensand
  • ¼ cup rock phosphate powder

Mix ingredients dry. Mix 3 parts dry mixture to 1 part water.

Larger Volumes:
  • 4 gallons sifted peat moss or coco fiber
  • 1 gallon sifted compost
  • 1 cup greensand
  • 1 cup rock phosphate powder

Mix ingredients dry. Mix 3 parts dry mixture to 1 part water.
Mixing tub suggestions: kitty litter box, cement mixing tray, wheelbarrow or a rigid baby pool.

Best tool for mixing: use an old-fashioned potato masher to mix water with dry mix.

Storage of unused blocking mix: allow the unused portion of blocking mix to dry out and store in a breathable manner. It can be re wet and used next time.

About the nutrients: In the event you cannot locate the nutrient ingredients perhaps you can find a substitute that is similar.

Greensand is used for its broad spectrum source of micronutrients as well as potassium.  It contains about 3% total potash, along with iron, magnesium, silica and as many as 30 other trace minerals.

Rock phosphate is a non-detrital sedimentary rock which contains high amounts of phosphate bearing minerals.

Click here for a printable version.