Have your plantlets grown too big for the windowsill?

Regardless of whether you're self-sufficient on a grand scale or grow vegetables in the corner of a balcony, the long wait until plantlets can finally go outside is something we've all experienced. You cultivate your favourite vegetables on a windowsill or in the greenhouse, tending to the delicate seedlings so that they grow into strong plantlets. According to the old Ice Saints proverb, most plants should not be put outdoors until mid-May at the earliest. But does that always apply? What should I do if my plants grow too big for the windowsill or are already starting to flower? We'll advise you on the conditions needed for transplanting to be successful even earlier.

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Impatient plant breeders and too much sunshine

Is my plant ready to relocate?

Everything you need for growing vegetables

Why are my plants so big?

Impatient plant breeders and too much sunshine

There are several reasons why plants might already be larger than usual. Did you start growing them too early? Since some plants – like the courgette – develop rapidly after germination, they should not be grown until mid to late April. That's why you should always pay attention to the periods indicated on your seed packaging. In addition to that, an especially warm and sunny spring can stimulate the growth of plants, making them flower earlier. Many hours of sunshine suggest, to the plant that the time has come to start flowering and develop fruit. If your plant is still standing on the windowsill at this point, then its flowers cannot be pollinated and fruit formation is prevented, which is disappointing both for us who were looking forward to some delicious vegetables and for insects in search of food.

Is my plant ready to relocate?

Since plants shouldn't be put outdoors too early, the first thing to do is check whether your plantlet really is too big for its current location. Check whether the pot is already well rooted. If the soil is still loose and only a few roots are visible at the edges of the pot, then it's quite safe to allow your plant to continue growing in it. If the soil is much firmer and a dense network of roots is already visible, then a larger pot might be the answer before you actually put it outdoors. If there's no way around moving the plant outdoors before the Ice Saints period is over, then we recommend the following:

Location
The perfect location when planting early is a raised bed which is sheltered from the wind because it's much warmer and the roots will not be exposed to frost. A roof or cover for the night provides additional safety. Plants in a pot can make themselves comfortable in a sunny spot, e.g. next to the wall of a building. This protects them from wind and heavy rainfall.
Watering
If at all possible, don't water your plants in the evening because otherwise the leaves and topsoil won't have enough time to dry off and there is a risk of freezing moisture.
Weather
Keep an eye on the weather forecast If the temperature drops below 3 °C at night, cover your plants with a thin translucent non-woven mat if possible.

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