CADL Seed Library

Resources

• How to Germinate Milkweed - from University of Texas Austin

• Cold Sowing (Stratification) - from MSU Extension

Notes

Many wildflower varieties, including milkweed and sand tickseed, do best when planted in Fall. Spring is a close second, however.

Milkweed and sand tickseed require cold stratification (or vernalization), which is a period of cold storage before planting that simulates winter. Ways to achieve:

1. Plant in the Fall and let nature do the work!

2. Place the seeds in a wet paper towel in a sealed container in the refridgerator for a few weeks, then plant in Spring.

3. Place the seeds in the freezer for a couple of weeks.

3. Really "dig into" the process and follow the steps linked above in Resources!

Milkweed - Common

• Days to germination: 28-42
• Days to maturity: 91-98
• Seed planting depth: .25"
• Plant spacing: 12-24"
• Light preference: Full sun

Seeds require vernalization before continuing with the following steps. Either plant out in the fall and let nature do the work or place the seeds in the freezer for a few weeks before planting in the springtime. Plant seeds outdoors directly into the prepared soil any time in spring or early summer. Water in the seeds with a mister. Optionally, begin the seeds indoors 4-6 weeks before the last frost date. Germinate the seeds at alternating temps of 60F at night and 85F during the day. Seeds germinate poorly in temperatures above 85F. When the seedlings have at least two true leaves, harden off and then transplant outdoors.

Growing info source: True Leaf Market Seed Company

Sand Tickseed

• Days to germination: 14-21
• Days to maturity: 100-300
• Seed planting depth: .25"
• Plant spacing: 12-26"
• Light preference: Full sun to partial shade

Coreopsis are easier to grow from seed. The only trick is stratification. All this means is that the seed coating is thicker than other seeds and needs to undergo some kind of process to signal germination. Common tactics are placing them in the fridge or freezer, or simply planting the seeds outside in the fall to get naturally treated over the winter. 

For Spring planting, place them on a wet paper towel in a sealed container in the fridge for two weeks before planting as normal.

Growing info source: True Leaf Market Seed Company

Purple Coneflower

• Days to germination: 7-21
• Days to maturity: 2nd year
• Planting depth: .25"
• Plant spacing: 48"
• Light preference: Full sun

Echinacea seeds can be sown directly after the frost but, for earliest spring blooming, begin indoors 6-8 weeks prior. Echinacea seeds will germinate between 7-21 days with full light and harden off if transplanting outside or to an indoor planter with full sun. Freely self-seeds if at least some of the seed heads are left in place. Echinacea is an adaptable plant known to be tolerant of drought, heat, humidity, and poor soils. Do not overwater.

Growing info source: True Leaf Market Seed Company