By Karen Cohen, Master Gardener/Photojournalist/Artist
Here’s a question for you gardeners to ponder. You obtain seeds online, from a friend, or in the store. Why don’t these seeds sprout inside their packets? They remain dormant until something coaxes them out of their seed coats. What factors initiate the process of seeds sprouting?
Many conditions have to be just right to cause a seed to burst open, send out roots and a shoot. Light, lack of light, moisture, soil temperature and air temperature, and the age of the seeds will all determine a seed’s ability to germinate. Some seeds require darkness, some prefer warmth, some need water. What we might consider as a miracle is actually a complex set of elements built into these tiny life packets.
We gardeners have learned how to encourage seeds to sprout in order to speed up the process of growth resulting in flowers or food for our benefit. Let’s learn about two processes we can use: stratification and scarification.
Seeds which require stratification will remain in their hard coatings forever if they don’t get stratified. What seems to be a mysterious process is very simple. Stratification is the process that imitates natural conditions of temperature and moisture to cause germination. I use the refrigeration method to accomplish this. First dampen a paper towel and then sprinkle on seeds in a row or randomly, it doesn’t matter. I decide how many plants I wish to create and then double that amount for seeds set down. Not all seeds are guaranteed to open up. Then I close up the paper towel, place it in a glass jar and pop it in the fridge, not the freezer. 35-41 degrees is perfect for cold stratification. Check daily to see if the seed has cracked open and sent out a little green “tail.” If nothing has happened, dampen the towel sparingly and pop back in your fridge. In a few days time, your seeds, if viable, will sprout.
Which seeds require stratification? Sage, lavender, sweet peas, sedums, lettuces, poppies, catmint, and leeks benefit from this process. An even easier method is called winter stratification. Now, in the fall, go to your pre-determined garden spot with whatever stratification seeds you have selected, pull back any leaves or mulch, toss the seeds on the ground and forget about them. Yes, the birds and squirrels will eat some but not all. Seeds have the built in knowledge to sprout when they are supposed to in the spring when the soil and air warms up. You can even toss this type of seed on snow, and lo and behold, they will sprout and grow in the spring. I am a firm practitioner of using marking labels for everything I put into the ground. Helps to keep track of direct seed sowing.
In the natural world, there are wildflowers that do their own thing by dropping their seeds late fall, go through the cold winter process on their own, and then emerge in warm temperatures.
A friend gave me a small plastic baggie filled with coneflower dried heads. Last week I crunched them up a bit in my hands and scattered all of them on the spot in my yard where I would love to see some purple flowers next year. Fingers crossed!
Scarification is another process. I remember this one by thinking of “scaring” something with a sharp object. Using a knife or a sewing scissor, knick the edge of a seed’s coating. Don’t cut into the middle, just the outer edge needs to be opened a little bit. This opening allows moisture to enter and hence, the seed sprouts into action. Plant these immediately in soil so that they don’t start to decay. Water a bit and voila! In a few days to a week, you will notice the seed sprouts.
What seeds require scarification? Really hard seeds like morning glory, peas, nasturtiums, lupines, beans, and okra can use help to germinate. This process of nicking each seed one by one can be tedious but it speeds up the process which could normally take a longer amount of time. Try it in the spring next year.
(Karen Cohen is a self proclaimed Mistress of her Organic garden, loves nature and is an avid explorer. Please email your tips and comments to email@example.com. Happy gardening!)