06
Apr
You can add considerable volume to your garden’s yields by starting seedlings indoors before the ground has even thawed. Set seedlings out after the last frost of the season has passed. You’ll be that much farther ahead than if you were just seeding the soil directly.
Garden centres sell starts every spring but these often come with a premium price tag & it’s difficult to get exactly what you want relying on a garden centre. Sooner or later all serious gardeners make the plunge into seed starting at home. In my opinion, the sooner you try – the better!
Getting Started with Seedlings
In a previous post we discussed the importance of planning to get the most out of your garden. That plan should include knowing how much of each crop you will need to fill your growing area. Each crop is either direct seeded or transplanted as a seedling. Direct seeding is fairly straight forward, but the transplanting part & the germinating before hand seem to intimidate many new gardeners. This is for no good reason!
It takes a bit of getting used to & some crops are fussier than others, but the pay off is certainly worth it. If all else fails, the garden centre starts will still be there. This way you will be developing your skills & challenging yourself. What’s more, by starting your own seedlings you have complete control. Everything from the varietals used, the growing medium, the fertilizers used are up to you. Perhaps most importantly, you can decide when & where to use pesticides. What’s more, the risk of importing any pests from the garden centre is all but eliminated by growing your own.
The investment of equipment for seed starting ranges from next to nothing up-to hundreds of dollars – it’s up to you & whatever your budget is. Don’t let the idea of expensive grow lights, timers, automatic misters or heat mats discourage you because they are out of your budget. At the end of the day, all you really need is a container to hold them, a growing medium, & some seeds. I need to remind myself often that seeds want to germinate; they want to grow. Sometimes they do so in spite of everything we have done that should have killed them!
DIY Potting Mix
If you want to try making your own growing mix there are numerous recipes available. Often the ingredients are easily sourced directly from the hardware store or your local greenhouse garden centre. If you are planning on doing some serious planting then this is a good way to save money by buying the inputs in bulk & mixing it yourself.
Here is a basic recipe for potting mix:
- 1 part vermiculite
- 1 part perlite
- 1 part peatmoss*
- 1/2 part sterilized compost
- 1/2 part sterilized garden soil
Mix the first 3 ingredients together well. This is the basis for your mix. You may need to add a bit of water, & be careful about breathing in any dust from the vermiculite or perlite. They can both produce a very fine powder which can irritate your eyes & airway. Pour slowly from the bag and mix in small amounts to begin with.
To sterilize the soil & compost, measure your quantities & spread them out in an oven safe container. Heat until temperature reaches 180 F allow to cool completely before incorporating it with the vermiculite mixture.
*I promote the use of peatmoss because we live in the North & peat moss is regionally available to us. Coconut coir is often suggested as an eco-friendly alternative to peat moss. The rationale is that peatmoss takes a long time to replenish and coconuts are a much faster renewing resource. The only problem with that is that coconuts then become a monoculture cashcrop – often in the global south – & there is little to no traceability guaranteeing best management practices being applied or laws being followed. That’s all to say nothing about the carbon footprint of shipping coconuts up to northern Canada. Do what you think is best for your own context.
Homemade Starting Containers
What Can be Used Instead of Trays?
Any household container that is waterproof can be used as a seed starting tray. You don’t need perfect individual cells, even, & I’ve met a few gardeners who actually find them more fussy than they are worth. Their preference is to plant all their seeds in one shared tray & prick out the best seedlings to pot up from the bunch. To each their own!
Milk jugs, egg cartons, toilet paper tubes cut into sections & laid on a plate – pretty much anything you have in the recycle bin could probably be used to start seedlings.
Invest in Quality Equipment
I have always used the standard black plastic trays. I spent hundreds of dollars at a box store one year only to discover that the heat in my greenhouse was too high. All of the cheap trays warped.
In retrospect what I really wish I had done was invest in a soil blocker & take the time to make some wooden 3 sided trays promoted by Elliot Coleman. These soil blockers come in a few different sizes & they do take a bit of getting used to. If you can use a cookie cutter though, you can use a soil blocker. The investment is made once & you have the blockers for life.
If you’re not sure what I’m talking about, you can see them here on Lee Valley’s website (I am not a Lee Valley affiliate – I just like the quality of their products & I use them)
How You Can Make Your Own Trays from Scratch
Admittedly the only time I have used up-cycled seed trays was in an egg carton & I wasn’t thrilled with the results. I found the trays to be too shallow and the seedlings were spindly. The pucks of soil dried out to quickly. The cardboard was floppy from watering & wasn’t easy to handle come time to transplant.
Thant being said – if you have a container that is ideally 5-7cm deep that is sturdy enough, give it a go! You may also want to invest in some toothpicks, & cover the tray with plastic wrap once seeded. This year as an experiment I am covering my trays with towels during germination. My hope is to keep the soil moist without using disposable plastic to do so. Once the seedlings germinate I will need to water throughout the day to keep them at a consistent moisture level.
Conventional Alternatives to Plastic Trays
While any container will do, the easiest, tried & tested commercial options are peat pots, pellets or fiber cubes. These are sometime called ‘Jiffy cubes” & they are quite convenient & readily available. Like the soil blocker they work by “air pruning” the roots to prevent seedlings from becoming root-bound. I stand by my assertion though that soil blocking is the absolute best for plant performance & environmental sustainability, however. I encourage anyone starting up to look into this method further.
Caring for Seedlings
Watering Practices
After your seedlings germinate be sure to water consistently for best results. Watering too often or too much can result in a damp-off where the seedling rots and dies at the soil level. Inconsistent watering can cause shock or stress. If you see the outermost seedlings withering and dying off – its likely due to inadequate watering. I like to to rotate my trays around every day or two. This accounts for any uneven surfaces causing water to pool at one end or the other of each tray.
I also recommend bottom watering whenever possible, and using a top mist only in the early days when the roots are shallow. top watering can spread fungal spores that may be on the surface. It can also disturb the soil & expose the seedlings’ delicate roots. Bottom watering has the added bonus of encouraging the seedlings’ roots to grow down towards the water source.
Choosing the Best Seedlings
If you opt to seed more than one or two seeds per plug then be prepared to make a judgement call on which seedling looks the hardiest & healthiest. Cull the rest as soon as it becomes obvious that one is the best candidate for your garden. It might seem counter intuitive, but crowding the plugs with multiple seedlings will only hinder their development. Less is more. If you don’t like the idea of culling seedlings then seed more sparingly. You’ll definitely want to use seeds with a guaranteed germination rate written on the package. If you do opt to cull secondary seedlings, simply snip them off at the soil level rather than pulling them out. Doing so risks damage to the root structure of your primary seedling.
Where you keep your seedlings is up to you but I recommend a warm, draft-free room with access to southern light whenever possible. The bathroom or the kitchen makes a great spot to get seeds started but don’t feel that they have to stay there. In fact, as seedlings grow it is necessary to ‘harden them off’ gradually by introducing them to stress like cooler temperatures, wind & direct sunlight. Do this incrementally so as not to overwhelm them. I recommend using an oscillating room fan placed at a distance to help seedlings grow a sturdier stem.
Feeding Seedlings
If you choose to use a commercial plant food, follow the directions regarding timing on the package. If you are feeling confident about doing things on your own then try making a compost tea & feeding it to them every other day. This nutrient dense plant food is used to boost growth & root development.
The following is my recipe for compost tea:
- 1 Gallon of water
- 1C of packed compost
- 1T of black-strap molasses
- 1T commercial liquid seaweed
Combine the compost with the water & allow to steep for a day or two. Strain through a sieve to remove large clumps & add the seaweed & the molasses & feed your seedlings as you would water them. Do so every other day & use the batch within a week to prevent it from going off.
Transplanting Your Seedlings
When it comes time to transplanting your carefully tended seedlings, begin by leaving them outside for a few hours a day, gradually increasing the duration of their time outside.
Do not tug on the seedlings’ stems! Either pop out the plug by pushing up on the bottom, or by using the flat edge of a butter knife to pry the seedlings loose of their flat. Again, soil blocks are superior in every way, but are especially efficient on transplanting day. There is little to no fiddling to loosen a plug from its tray. Just pop that seedling block right into the ground & move on!
When to Transplant
Transplanting is best done on an overcast day with no wind. The direct sun will dry out the seedlings before they have a chance to naturalize. If this isn’t possible, then transplant in the late afternoon or evening and water generously. Feel free to water with an addition of plant food or compost tea for an extra boost.
If you have shade cloth consider sheltering your seedlings from the direct noon hour sun for the first few days after transplanting. Likewise, if there is an unexpected risk of frost then cover seedlings with garden fleece, row cover or a bedsheet if that’s all you have on hand. Plastic milk jugs filled with water can collect the sun’s heat & radiate it back out to neighbouring seedlings if the risk of late frost worries you. These passive solar heaters work best under cover.
Get Gardening!
That’s really all there is to it! Starting your own seedlings at home absolutely does not have to be a prohibitively expensive endeavor. It also doesn’t need to be so technically challenging to do that it is above the average gardener’s skill level. Remember what I said earlier about seeds wanting to germinate. They’re designed for it!
Check back in the fall for my follow up post on seed saving. In the meantime – happy gardening! Be sure to let me know if you have any tips or tricks not mentioned here that work well for you. If this is your first year starting seedlings at home please let me know how it goes!
