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Light for Seedlings: Is There Such Thing as Too Much?

Starting plants from seed is a cost-effective, rewarding experience that is relatively easy to do. Although the steps are fairly simple to follow, when starting seeds indoors, one wrong move could be the difference of successfully growing your seedlings to ultimately failing to get them to sprout and/or survive. Proper care is essential for success.

seedlings under lights

One common mistake in starting seeds is supplying the right amount of light. Yes, it is true that your seedlings need lots of bright light to grow healthy and strong—but they also need a period of darkness in order to thrive. In general, seedlings should receive roughly 14 to 16 hours of light a day when situated in a south-facing window. This can be very difficult to achieve, and most growers opt to use artificial lights for their seedlings. These fluorescent lights should be left on for 12 to 16 hours a day. Many people make the mistake of leaving their seedlings under fluorescent lighting 24 hours a day. This does not make them grow faster, and can actually hinder the success of your seedlings. Remember that specific lighting requirements may very depending on the type of seed being sown, so it is important to research your plants’ specific growing needs.

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