Seed Starting Workshop
February 28, 2010
Alberta Ave Community League
Written and Presented by The Garden Diva (Cheryl Walker)
One of the biggest challenges with growing things in Edmonton – zone 3A is our short growing season. While our days are longer than many other more temperate regions, we still don’t have many of them in a summer. One of the ways around this is to start plants ahead of the gardening season. Starting your seeds indoors is a simple and cost-effective way of increasing your garden size.
The process of germination is not magical, but it does require us to pay attention to what we are doing.
Growing your own plants from seed takes a few inputs, so let’s consider them in turn:
Seeds – You can procure your seeds from several sources, I’ve included a few in my list of sources below. Additionally, you can procure all manner of seeds from hardware stores, nurseries and greenhouses, even grocery stores. Try to ensure that wherever you buy your seeds, your bulbs or corns from has sufficient turnover, they aren’t pulling out stock from last year and trying to foist it off on you. While you can absolutely store seeds, this has to be done properly to ensure germination occurs.
Have extra seeds left over from year to year? No problem. Store them in a cool, dry place. I use a metal cooky tin in my basement. Keep them away from moisture, humidity, and bright light. Sow a bit more thickly next year. I’ve used the same package of cherry tomato seeds for 3 years.
A growth medium – You can buy a wide variety of growth mediums, from compost based, to peat based to dirt. NEVER use dirt from your garden or your house plants – you must use sterilized dirt. You can sterilize dirt in your oven, on cooky sheets at 350 C for an hour, but I warn you, it is a stench unlike any other. Buy new each year, and use what might be left over to add to the dirt component in your compost.
A container - There are as many options for containers as there are gardeners. I like plastic because I use it from year to year. Some people use 2L milk cartons, egg containers, yogurt cups, peat pots, they hang on to the plant cell 6-packs they get their annuals in, this part doesn’t have to be expensive. Do remember to account for adequate drainage, and sterilize your plastic containers before each use. I do this at the end of the spring when all my plants from that year are in the ground. I take a bucket, add about a half cup of bleach, and scrub out my plant containers. Kills the dandelions and cleans my plant starting stuff. I store it in the garage until spring. If you use peat or coir pots make sure you slash cuts in the sides to help the roots extend past the pots.
Water - For the first few weeks, you won’t water much at all, using the evaporation/condensation cycle in your seed starting trays to keep your plants moist. When the seeds have germinated and are getting close to brushing the top of the plastic dome, you will need to remove the dome. Water as much as possible from the bottom, and never, ever allow them to dry out. Some gardeners use watering mats.
Light - Light is particularly important to seedlings, and a great many of the problems you will encounter have to do with light. In Edmonton, it should come as no particular surprise that we constantly struggle for enough light. If you are fortunate enough to have a window that gets at least 6 hours of bright, direct sunlight a day, and you are only starting a small number of seeds, then this will probably work. If you don’t have enough light (and be pessimistic in your estimates, no point in going to all the work of planting only to have your seeds rot), you will need to use a grow light, as discussed in class.
Heat – Seeds need warmth to germinate – which means that you have a few options. You can look at the plant warming pads from somewhere like Lee Valley, while particularly expensive, they do allow you to start your seeds in a colder place, like a basement. Alternatively, you can simply start your plants in a warmer spot – around 23-25 degrees Celsius.
Air Circulation: Seedlings need air circulation around them to strengthen stems and to keep mould and mildew at bay. The best way is to point a fan at them.
Thinning: Sooner or later you will need to thin out your seeds. Chose the single, biggest and best looking sprout and gently pluck all of the others out. Ideally, do this when your best specimen is at the cotyledon stage (2 leaves)
Fertilization: In a word – yes, but not for a few weeks – again once you have everything at the cotyledon stage, and then in very small amounts. Quarter the suggested amount, and slowly work up. Fertilize about once a week.
Conditioning to temperature: Most seedlings will be ready to go in your garden around May 7th (the average last frost free date in Edmonton). A few weeks before this, start getting your seedlings used to the outdoors. Place them in the shade at first, in the warmest part of the day. Slowly move them into more direct sunlight and have them stay out longer.
Repotting: Depending on what you grow, you may need to repot. Repot when something appears to be quite root bound. To do this, simply pop the plant, dirt and all out of its old container, and plant into a new one. Do not put a peat pot inside another peat pot.
Vesseys Seeds Canada : http://www.veseys.com/ca/en/
Richters: http://www.richters.com/ (Herbs, both culinary and medicinal)
Upper Canada Seeds: http://www.uppercanadaseeds.ca/ (Heirloom Seeds)
Apache Seeds: 10136 149 Street Northwest
Lee Valley Woodworking and Gardening - www.leevalley.com or 8403 104 Avenue Northwest
Holes Greenhouses – St. Albert