Winter Sowing
Winter sowing is a really cool technique! Forgive the pun (that was a bad one) but when winter sowing the gardener creates mini-greenhouses that protect the seed from some elements (like critters and wind) while allowing them to be exposed to others like temperature fluctuations!
- Just take a used plastic container. Milk jugs, juice containers, butter containers, or even yogurt cups will work.
- clean it out - important step here.
- add some drainage - also important
- cut around the container to leave a hinge
- add soil - gotta have it.
- add seeds - very important step - indeed critical
- water - do I need to point out that water is critical too?
- then tape the container shut.
- Place in a semi-shady place outdoors and let nature take its course.
Scatter Sowing
I scatter sow quite a few things in the garden. Generally anything that has small seeds that I can either thin out or want a whole bunch of gets scatter sowed. Lettuce and basil are two of my favorite scatter sowing plants. Both have small seeds that respond well to light exposure. When you scatter sow (or broadcast sow as you may want to call it) you let the seeds land on the surface of the soil and water them. Small seeds benefit because they need the light to germinate. It's also a really easy technique for the lazy gardener!
- Just clear an area of weeds,
- lightly tamp it down,
- scatter the seeds on the surface of the soil,
- and water.
Keep it watered as needed until germinated and beyond! You can do the same technique with wildflower seeds too.
Starting Seeds Indoors
I start many of my seeds indoors on flats with heat mats. While I say indoors these are actually in my garage under some shoplights. Is a garage indoors or outdoors? Or does it depend if its open or not? In either case I'm getting heucheras and hostas ready for this year's production! In mid January I'll be getting tomatoes and other vegetable plants started in flats like these with a plastic "dome". The dome keeps the heat and humidity in the flat where the seeds need it. I have a thermostat set to 70 degrees for these heucheras and hostas. When starting seeds in the garage the heat mat is a necessity but when you do seeds indoors the ambient temperatures of the room may suffice. Lighting though is critical! Some seeds don't need light to germinate while others do but all need light once they have germinated. In general the smaller the seeds are the less deeply you should cover them with soil when you plant them. For teeny tiny seeds (like heuchera) I'll just scatter them on the surface of the soil.
Update 2013: I began using plastic cups as small greenhouses in addition to the large flats. They create a terrarium-like environment that keeps the seedlings moist until they are ready to transplant. I can grow 20 seedlings in each cup with ease which makes them a great space saver!
Cold Stratification
Cold stratification is where you simulate the natural cold temperatures that eventually break through the seed coat and trigger germination. In the picture below the dogwood seeds have been stripped of their fleshy outer coat and placed in plastic bags with moist sand. When warmer days are in the forecast I'll plant these seeds into pots and hopefully get to enjoy some white dogwood trees.
I also store many of my seeds in the refrigerator in a plastic box next to the yogurt and oranges. The cool temperatures help to preserve viability and also may help them to stratify if needed. This is our second refrigerator so don't worry, my seeds don't replace our food!
Scarification
Scarification is a useful technique for those tough shelled and tough to germinate seeds. Essentially you chip through the shell to create an opening for water to get into the embryo. There are a couple ways you can accomplish this. One method uses sandpaper to scuff up the outside of the seeds. Just place the seeds on a flat surface and gently rub the sandpaper over the seeds. This works for smaller sized seeds. Another method actually chips into the seed. Use a knife or a pair of nail clippers to create an opening through the seed coat. Scarification is a great way to help redbud seeds germinate. Sometimes they need both stratification and scarification. With scarification just make sure you aren't borrowing your spouse's best pair of nail clippers...
Hopefully this post is getting you fired up about starting some seeds this year! I'm already growing - and I haven't even started on the holiday goodies yet!