The process is officially termed ‘hardening off’. In these days of bootcamp this and extreme that , it’d be rebranded ‘toughening up’.
It’s the process of taking a plant; a windowsill wuss and making an outward bound, fruiting machine out of it. Along the way expect a few Grenadier style, hot weather, forward flops.
This is one of the Seeds of Italy plants getting used to being outside. As you can see it’s taking standing at ease to a whole new angle.
The cause: Transpiration. All plants lose water vapour. About 95% of the water which a plant takes up through its roots, leaves through its leaves. Usually the amount of water vapour going out is adjusted in line with the amount of water being taken in. Thus ensuring the plant remains turgid. Stomata on the leaves open and close guard cells to make this adjustment.
But when plants are first outside they require time to re-regulate. Even if it’s no hotter the breeze/wind factor will be more drying for a plant than inside.
The answer – a long, cool drink. This is the same plant less than an hour later. Back on parade !
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It’s Italian – shouldn’t you be feeding it coffee?
My plants were used to being roasted for several hours on sunny windowsills, but when I was hardening them off last month, a few went limp like yours. I’m glad they recover so quickly. Once you plant them into big containers (or soil in my case) they’ll be happier campers, getting their roots down to some serious moisture-grabbing.
Interesting post, thanks.
I agree – it’s the quick recovery after the emergency watering that’s so impressive – and so welcome. It’s when you look out the window and see they’ve all keeled over and your heart stops that’s the worst. I reckon tomatoes have a black sense of humour when it comes to orchestrated ‘let’s all fall over and pretend we’re dying’…. they think….that’ll get her out here double quick with that water….
I use a small fan the last week indoors. That seems to toughen them enough. The stem also gets stronger.
Great tip!
Undertaking the process indoors would also save many days of carrying them in and out of the house! Which is a time consuming activity – although it also means I get stronger as well as the plants!