I am starting to grow summer flowers from seeds
something like Petunias amongst others.
I have a sunny room, can i put the seeds tray in this room,even if some sun will be right on them for a couple of hours or in the center of the room,only to get the light or just stick to the grow lights???
Hi Amjad, I would be inclined to just use the grow lights until the plants are bigger.
Sunlight is too intense, and the soil can dry out so quickly that you could lose all your newly germinated seedlings within a few minutes.
If you have a sheer (very thin) curtain across the window, this might work, but please keep an eye on them, especially if you're using domes to keep the moisture in; they can cook at too high of temperatures.
Move the little plants there once they have their first real set of leaves to harden them off (a fancy way of saying, get them used to the big, big world).
The other important aspect of light is daylength or photoperiod, the amount of light that the plants get over the day. Short daylight hours can cause early blooming in some plants, otherwise known as 'bolting'.
Another issue is stretching or etiolating, which means that they are reaching for more, and this is really hard to deal with after the fact.
Avoid it by putting the seedlings only a few inches below the grow light, if you're using fluorescent tubes so they get all the light they need.
Hope that helps, keep me posted.
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