NOTE: This product is a pack of 10 seeds.

How to Germinate Yellow Iris Seeds

Growing irises from seed can be a longer process than growing from rhizomes, but it allows you to grow many plants economically. Many iris species, especially water-loving ones like the Yellow Flag Iris (Iris pseudacorus), have seeds that require a period of cold, moist conditions to break dormancy—a process called stratification.

1. Understanding Iris Seed Germination

• Dormancy: Iris seeds have a built-in dormancy mechanism that prevents them from sprouting at the wrong time of year (e.g., right before winter).

• Stratification: To break this dormancy, the seeds need to experience a "winter." We can simulate this with a process called cold, moist stratification. Without this step, germination rates will be very low, if they happen at all.

2. The Germination Process

Step 1: Soaking

• Begin by soaking the seeds in warm water for 24-48 hours. This helps to soften the seed coat and allows the seed to absorb moisture, which is the first step in waking it up.

Step 2: Cold, Moist Stratification (The "Winter" Simulation)

This is the most important part of the process.

• Materials:

  • A small zip-top plastic bag.

  • A sterile, moist medium like peat moss, vermiculite, or a paper towel. The medium should be damp, like a wrung-out sponge, not soaking wet.

• Method:

  1. Place the soaked seeds into the damp medium inside the plastic bag.

  2. Seal the bag, pushing out most of the air.

  3. Label the bag with the date and the name of the seeds.

  4. Place the bag in the refrigerator. The vegetable crisper drawer is an ideal location.

• Duration: Keep the seeds in the refrigerator for 60 to 90 days. Check on the bag occasionally to ensure the medium hasn't dried out.

Alternative Method: Natural Winter Sowing

If you are starting in the fall, you can let nature do the work.

1. Fill pots with a good quality seed starting mix.

2. Sow the seeds about 1/2 inch deep.

3. Place the pots outdoors in a protected location where they will be exposed to the cold, rain, and snow of winter but safe from pests.

4. The seeds will then sprout naturally in the spring when the weather warms up.

3. Sowing and Sprouting (After Artificial Stratification)

• When to Sow: After the 60-90 day cold period is complete.

• Planting:

  1. Fill pots or seed trays with a sterile seed starting mix.

  2. Sow the stratified seeds about 1/2 inch deep.

  3. Gently water the soil and keep it consistently moist but not waterlogged.

• Location: Place the pots in a location with bright, indirect light at a cool room temperature.

• Timeline: Germination can be slow and sporadic. Be patient. You may see sprouts anywhere from a few weeks to a few months after sowing.

4. Caring for Seedlings

• Once seedlings have emerged and developed a few true leaves, you can begin to fertilize them with a diluted, balanced liquid fertilizer.

• When they are large enough to handle, transplant them into individual pots.

• Harden them off by gradually acclimating them to outdoor conditions before planting them in their final location in the garden. Yellow Iris (Iris pseudacorus) is an aquatic/bog plant and thrives in wet soil or even in shallow water at the edge of a pond.

Note: Irises grown from seed will typically take 2-3 years before they are mature enough to produce their first flowers.