Laidback Gardener Tip of the Day Recycling Sowing Seeds

My Sowing Kit (or Ode to the Mushroom Tray)

When I say that I have grown from seed Canadian rhododendrons, primroses and rare alpine plants at home, people often get the impression that I am working with ultra-sophisticated equipment or that I have a hi-tech greenhouse! And yet, it is quite the opposite. My sowing kit is mainly made of recycled materials.

Part of my sowing kit. Nothing fancy! Image: Julie Boudreau.

Seedling containers

Look at this splendid mushroom tray full of germinations, ready to eat! This is, in my opinion the perfect container for seedlings. Image: Julie Boudreau.

To make seedlings, it takes pots. And it’s all there, in the recycling bin. Small yogurt containers and plastic pots of all kinds. Personally, I have a favorite: the mushroom tray. It is the ideal format for sowing on a family scale! Indeed, the mushroom tray contains just enough tomato seeds, annuals or parsley to meet the needs of my little household, including gifts to neighbors and friends. With a pair of scissors, I make a few small cuts in the bottom of the container to ensure drainage. It is essential that containers for seedlings have drainage holes. For some time, I have been buying cherry tomatoes produced locally that are sold in cardboard trays. In the same format as my adorable mushroom tray, this one has the advantage of being compostable, which makes it more ecological. They will be tested soon!

Looks like my actions are quicker than my thoughts: I found a cardboard tray in my germination mix! I am guessing that I will use it only once. Decomposition is starting to do its work (I took the beautiful side in picture). Image: Julie Boudreau.

For some seedlings, such as squash and cucumbers, pots can be made from strips of newspaper. These paper containers can be planted directly in the ground in the spring.


Anyone who sows has extra seeds… a box full of extra seeds! The first step is to take advantage of an innocent visit to friends to slip into the conversation the plan to start seedlings. It doesn’t take much for the magic box to end up on the table and for the seed envelopes to pile up. The other option is to attend a Seedy Saturday. It is there, at the Seedy Saturday, that I select the varieties that will be tested in my garden. These free activities are great times to connect with talented organic seed growers. I let myself be influenced by my seed growing friends and it always gives good results. This year, I’m trying my luck again with soybeans, edamame and chickpeas. The ‘Malinalco’ tomatillo, the ‘Puztakolosv’ tomato and the ‘Prune Mauve’ radish are also part of the vegetable garden program.

The transparent dome

Our freshly sown seeds must benefit from a high level of humidity. Generally, a transparent plastic dome is used. I have a few of those. But let’s face it, the large trays of croissants are just as effective. You can also replace the dome with a simple transparent plastic bag, held in place by a few sticks. In short, anything transparent can be used to maintain high humidity around the seeds.

The seed trays and my sowing shelf: the perfect duo!

As a tray to receive my containers, I use black trays without holes as sold in the market. However, I try to get those for professionals, which are thicker and therefore more solid and durable. I reuse these trays until they are completely exhausted. When they pierce, I stack them with other perforated trays, just to prolong their usefulness as much as possible. I use this large tray to collect excess water. It could easily be replaced by a saucer, a plate or a plastic cover. But the black plastic trays have the perfect format for my seedling shelf, the one I built myself with recycled wood. Easily retractable, I store it in the basement for the summer and reinstall it with the first snowflakes, just to start with microgreens and mescluns so I can survive the winter!

The soil, yes I give up!

The only item I recommend buying new is potting soil, especially when you are just starting out. Old potting soils are sometimes contaminated with fungal spores which can cause damping off. They are also less absorbent. Put all the chances on your side by working with new soil. Moreover, surplus soil for seedlings can very well fill decorative containers and flower boxes. Nothing is lost…

The tags

Tag production in action! Image: Julie Boudreau.

A seedling without a label is the announcement of an impending disaster! It seems superfluous, but it is not, especially when you sow 6 varieties of tomatoes per year! Not easy to recognize them by the leaves… Here, I use all possible strategies! First, a cleaning of the “cupboard”: a hodgepodge of recycled plastic pots and yogurt pot covers. Anything that doesn’t find its soul mate instantly becomes tag material! I cut everything into small strips just wide and long enough to write the date and the name of the plant. I have long used old horizontal blind slats and sometimes popsicle sticks.

All this to show you that you can, with a little imagination, find seeding material among these materials that deserve to have a second life (and why not a third and fourth life). And, in the same logic, it is not necessary to pay for expensive equipment to succeed in sowing as well as the professionals. The Laidback Gardener’s Blog is full of articles on indoor seeding techniques. But seriously, the mushroom tray… how wonderful!

Julie Boudreau is a horticulturist who trained at the Institut de technologie agroalimentaire in Saint-Hyacinthe, Québec. She’s been working with plants for more than 25 years. She has published many gardening books and hosted various radio and television shows. She now teaches horticulture at the Centre de formation horticole of Laval. A great gardening enthusiast, she’s devoted to promoting gardening, garden design, botany and ecology in every form. Born a fan of organic gardening, she’s curious and cultivates a passion for all that can be eaten. Julie Boudreau is “epicurious” and also fascinated by Latin names.

4 comments on “My Sowing Kit (or Ode to the Mushroom Tray)

  1. jessica crawford

    Love those perfect mushroom boxes for seeding & just storing stuff. And they stack so nicely!

  2. Jt Michaels

    Oh Julie, finding planting uses for all the plastic we are often forced to bring into our homes from the grocery stores (if we want to eat anything fresh in the winter) is a brilliant example of reuse. I did it for years! Thank you for sharing the idea with friends on this blog.

    Because I’ve found ways to get around all the plastic (it’s not easy!) I’ve used both cardboard/waxed half gallon milk and pint cream containers for more than a decade. I’ve found they, if handled properly, will last two or more seasons before they begin to breakdown. Once the wax (or whatever it is) has deteriorated enough to make the milk pots unusable, I’ve found the containers decompose nicely.

    • Julie Boudreau

      Indeed! Not bringing in those plastic container is the ideal goal and yes, cardboard containers are a great alternative. Reusing is good, reducing is better!

  3. Kirsti Reynolds

    Plastic knives, spoons and forks work well as labels too.

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