When to Pot Allium Seeds

Collecting Allium Seeds

• There are two ways to obtain allium seeds for potting. Either purchase them from a seed company or collect your own from the garden. Collect allium seeds in the fall when the flower heads begin to dry on the plant. Cut the flower heads from the plant and shake the seeds into a bag or bucket. Replant the seeds within a few weeks of collecting or store the allium seeds for the winter. A jar with a tight-fitting lid in the back of the refrigerator makes a good storage solution.

Potting up Allium Seeds

• Use a seed-starting flat or individual 2-inch pots or cell packs. If you have a bunch of larger planting pots around, use those and plant multiple seeds in each pot. Use seed-starting compost or seed-starting mix to germinate allium seeds. A sterile seed-starting mix made from equal parts peat, sterile compost and coarse grit works well. Fill the seed flat or pots with the damp mixture and level off the top. Plant the allium seeds 1/4 deep and 1 inch apart.

Fall Planting

• Replant the seeds in the fall within a few weeks of harvesting. Place the pots outdoors in mild climates or, in cold climates, keep the pots in a cool greenhouse. The seeds should be kept cool but not frozen. Keep the soil in the pots between 35 and 40 degrees F for the winter months. The allium seeds will go through a natural chilling process during the winter and will germinate in the spring.

Spring Planting

• Remove the allium seeds from the refrigerator in the spring. The seeds go through the necessary cool period in storage and are ready to germinate once they are potted up. Plant the allium seeds in pots and place the pots where the soil temperature will remain at or slightly above 55 F. Keep the soil damp around the seeds. Look for new, green seedlings 10 to 12 weeks after planting.