Growing Perennial Flowers from Seed
Most native plants need to go through a period of cold weather in order to be able to germinate in spring.
Therefore collected seeds need to be cold moist stratified.
There are different ways to do so:
Let winter do it naturally through outdoor cold moist stratification
or mimic conditions in your fridge.
Getting Started in Spring
to Grow Your Own Native Plants from Seed
What you need:
Heather McCargo, founder of the Wild Seed Project is an excellent source to learn more about seed propagation.
She has decades of experience with a wide variety of native plants, methods and soils. The featured talk will carry you off into the wonderful world of growing your own native plants from seed and contributing to genetically diverse seedlings.
It is surprisingly easy and cheap to grow your own garden from seed
Here Is How
Containers & Soil
Any container that is at least 5 cm / 2 inches deep can be used.
If the container doesn't have drainage holes, cut holes in the bottom.
Any potting soil is sufficient, there is no need for seed starting mix.
Most soil comes rather dry. To safe time you can pour quite some water into the open bag and let the soil absorb it for some hours. Soil needs to be evenly moist before sowing.
Fill containers and tap it to settle the soil until the container is almost full.
Leave about half a centimetre of room at the top.
Sowing Your Seeds
Put seeds on the palm of one hand, pick the seeds you will sow and sprinkle them as evenly as possible onto the soil.
Very gently press them into the soil and add a dusting of soil on top. As a rule of thumb, seeds should get covered with soil about their own thickness. Smaller seeds often need light to germinate and therefore should just be sown on the surface.
Water gently to settle the seeds.
It is a helpful to mark every container with the species and the date of sowing.
Cut-up yoghurt containers work very well to create your own tags.
Depending on your area, you might have to protect the pots so that squirrels can't dig up the soil and destroy the seedlings.
The easiest is to use a sturdy plastic netting.
Chickenwire is a method that works very well - but working with chickenwire is quite unpleasant unless you build a cage that you can use for years.
It is surprising how effectively simple plastic bags prevent squirrels from digging. This method also creates a greenhouse that provides a warm and moist environment that is ideal for germination even up to 1.5 months earlier than without this protection. As the evaporating water condenses and drips back into the soil watering needs are reduced to a minimum.
See-through containers with a matching bottom from the kitchen recycling can also be made into squirrel-prove greenhouses.
Caring for Your Seeds
Seeds will sprout on their own pace depending on day time temperature, night time temperature, moisture and light conditions.
Once the seeds have sprouted and are small seedlings they should never dry out. Monitoring and watering is essential.
Once the seedlings have their second set of true leaves (cotyledons are the very first leaves that often don't look like the plant's leaves) it is time to up-pot the seedlings. Divide them into pieces of about a square inch and put them - just as they are as one piece - in the middle of a bigger pot. This way the roots don't get damaged and they have space to move outwards.
Since potting soil has fertilizer added and most native plants, particularly prairie plants, thrive on poor soil there is no need to add fertilizer at any time.
Ready to Be Transplanted
Most Plants Will Be Ready To Get Transplanted By Summer
It is important to match the plant to the right conditions of a location so that the plant can thrive.
Even drought tolerant plants need frequent watering until their root system is well estabished.
Outdoor Sowing in Fall
A good time to sow outdoors is late Fall. Most weed seeds have been dispersed and will not fly onto your pots anymore and work can still be done outdoors. For the seeds to get enough cold moist stratification time plant anytime before February.
Any plastic container with a minimum height of 10 cm (3 inches) is ideal. You can get one more use out of recycling kitchen containers or roll up thick layers of newspaper to create your own pots. It is important that the containers have holes on the bottom to let extra water drain. It is equally important that the potting soil is wet before filling the containers. If your bag of soil has dried out, just add water. You can either wait until the soil has absorbed the water evenly or you can mix it in with your hands like you would knead dough. Fill containers with soil and press that the soil is rather firm. Then add some more soil that is not too compacted.
Keep Outdoors Over Winter
If sown indoors, bring the freshly sown pots outside in a sunny location where the rain can reach and the snow will be able to cover them.
It is recommended to protect the seeds against squirrels by covering with mesh.
To give extra protection cover with a layer of leaves.
Any cages on top can also be used.
The Seeds Will Germinate In Spring
Once the danger of frost is over, take off the leaves so your seeds receive more sunlight. Once your seeds start germinating, it is important to make sure they don't dry out. From now on check daily if the soil needs watering.
Stratifying the seeds in the fridge and planting outside after the last danger of frost is also a very successful method.
Keep the seeds in the paper seed packages until mid of February.
Transfer seeds onto a moist paper towel.
Put paper towel into a ziploc bag.
Keep bag in the fridge till last danger of frost has passed.
Plant outside in containers filled with well moistened potting soil.
Put in a sunny location.
Keep well watered.
Seeds will germinate at very different rates depending on their species.
Seedlings are ready to transplant in summer or fall.