Free Shipping on Seed Orders over $50. (not including Potatoes, Garlic, or Bulk Seed)
Has it ever happened to you as a gardener to get excited in May, only to take your beautiful indoor seedlings outside and watch them yellow, burn, or even die because of a late frost?
The problem isn't the cold; it's the shock your plants experienced.
In this article, we'll discuss an infallible method to harden off your beautiful indoor-sown plants and prepare them to face the harsh reality of the spring climate in Quebec.
We know that in many regions, the last frost will arrive around the end of May or even early June. But it's still a good time to start preparing for the acclimatization phase.
Let's start by explaining a bit about what hardening off (acclimatization) is. We know our indoor seedlings are extremely well cared for. We maintain a constant temperature, adjusted light, and there is no wind inside... So, our beautiful indoor plants are truly pampered.
The consequence of this is that our plants get used to growing in these conditions and do not develop the cellular structure strength to resist the climate they will have to face when they are outdoors.
We are thus left with plants that are not ready to face the sun, wind, and cold, which are all inevitable.
And if we take them out too quickly, without taking a one to two-week acclimatization period, what will happen is that the leaves can burn due to sunburn or the wind can even break their stem, which may be too tender.
Okay, you want to acclimatize your plants this year, putting all the chances on your side, but how do you do it?
I'm going to give you the ultimate technique, if you really want to pamper your little plants.
Warning: At the farm, we can't give that much attention to our thousands of small plants, so it is not always absolutely necessary to be that cautious, but I will still explain the ideal technique to you.
Hardening off requires 7 to 14 days before the scheduled date for outdoor planting.
Here is the ideal progression:
After two weeks of acclimatization, you will be able to transplant your plants directly outside into the garden.
Choose a cloudy day to minimize shock as much as possible.
Gently untangle the roots if the root ball is very compacted. This allows the plant to recover faster and have better rooting. Be careful not to break everything, however.
Water thoroughly immediately after transplanting. This really helps plants adapt better, while always avoiding falling into excess.
Once transplanting is done, it is essential to keep an eye on the weather forecast. If a late frost is announced (often around the full moon), you will have to take measures to protect the plants, because you will no longer be able to simply bring them back inside; you will have to cover them.
So now you know you need to give them a little time for acclimatization and adaptation, and how to transplant them, but what date can you take out your famous tomato plants?
The answer will really depend on where you are in Quebec. Tomatoes, peppers, basil, cucumbers, zucchini, and melons are all plants that are very sensitive to frost.
To garden safely, we want to plant them only once there is no longer a risk of frost. And that will depend on your hardiness zone (zone 3, 4, or 5). Depending on that, your planting date will be from late May to early June, depending on your region.
If you are a slightly impatient gardener, thelow tunnel (or row cover) is an excellent technique. It will allow you to take your plants out a little before the risk of the last frost and will offer you the tools to easily protect them in case of an early frost.
This technique involves placing galvanized wire hoops over your rows, then covering them with a material.
The benefit and protection of this small tunnel will really depend on the material we use.
Floating row covers are generally categorized by their weight in grams per square meter. The smaller the number, the lighter and thinner the cover is, the less it protects against heat, but the more it lets light and water pass through.
Here are the main options you can find at suppliers like Dubois Agrinovation:
NovaGril P12: This is one of the thinnest covers. It lets through a maximum amount of light (about 90%) and offers very slight thermal protection. It is mainly used for protection against insects (carrot rust fly, flea beetles).
Agril P17 or Novagril P19: These covers are thicker and ideal for creating a small microclimate without the risk of overheating. They are very good in early spring. You can gain 2 to 3 extra degrees with this, which can help protect against light frosts overnight. The P19 is slightly more durable than the P17.
BioPlus P30: If you plant very early and fear severe frosts, this cover offers superior thermal protection. However, it lets through less light.
It is also possible to use apolyethylene plastic film on the hoops as an alternative to floating row covers.
Plastic allows you to achieve maximum warmth and can increase the temperature when it's sunny. However, you must be very careful:
1. Water Management: Unlike floating row covers, plastic does not allow water to pass through, which will require careful irrigation management.
2. Ventilation: When it is sunny, the tunnel can overheat very quickly, risking burning your plants. Regular ventilation is crucial.
You now have the tools to successfully harden your plants off and protect them from the cold in the early spring.
I invite you to think about your strategy for hardening off your plants: where will you put them initially (where they are very protected) and where will you gradually expose them to the elements?
Don't forget to get what you need (row covers, hoops) to protect your plants in case of a late frost.
Cheers!
👨🌾 Frédéric
100% Organic
No GMOs
++ Biodiversity
Leave a comment (all fields required)