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Started growing my seeds today

Am I mad, am I in a coma, or did I get a hydroponics set up geared towards the first stage of growth?

The world of hydroponics is weird, and the information available on the internet is for people growing “indoor plants” which have completely different requirements to outdoor plants. There is also a whole different set up needed for greenhouse stuff but that’s a different story.

This information is simply for starting seeds off in trays and keeping them happy and growing until its Safe for them to be planted outside. 

first of all a single Chinese LED grow light lightbulb in a lamp will not work for seedling propagation.  It will help if you have a unhealthy looking cactus but not seedlings.  You need four 22w LED lightbulbs for a single small seed tray and they need to be about six inches above it. When you factor in the cost of lamps, bulbs and figure out how to plug four lamps into the wall buying a proper set up becomes worth it. 

 Your lightbulbs also need to contain enough blue light to promote vegetation or they will grow leggy and you might as well have left them in the window. I cannot stress enough that unless you have enough blue then your set up is as useless as a chocolate teapot. 

There are very few real options available to you if you just want to put the darn trays under something that works without needing some sort of science degree to figure out. The two types I am recommending are the easiest way, but if you want to go industrial and hang lights off bookshelves and whatnot then go for it, just remember about the blue. 

1. Garland grow light garden type, full spectrum tubes suspended above a tray or on legs.  Will grow fine but when  the bulbs go it costs you around £10 to replace each one, a small concern as they last so long but something to note. You need four tubes for two full sized seed trays.   

2. Option I went for because I have a space issue. Root!it LED grow lights, two of them for a large Stewart premium heated propagator. down side and upside to this is that they sit on top of the propagator, so although it uses up less space you also can’t start propagating anything else until your plants are big enough to be moved on.  You can also buy lighted propagators but they are exactly the same as buying separately and cost twice as much.  

I’ll post a picture in the next post because if the forum glitches  up on me because if it after this wall of text I may Cry. 

In summery;  Blue light is good, blindly strong light is good. Putting the plants you have grown under lights out too early is bad. 



  • So yup. this is my set up.



    I got some pansy, daliah and some cauliflower in there, cauliflower can go out a lot earlier into the cold frame, flowers will be fine to live there until they are potted on and hit the propagator roof if I like. 

  • I may be posting to an empty room here but ok.

    Lights on on heat off on Day 3. Daliah sprouting nicely. Cauliflower just showing, pansy showing small signs of life.


    Last edited: 19 February 2018 11:18:32

  • DimWitDimWit Posts: 553

    It is funny that pansy seeds would need heating to sprout. It is summer here in Brazil and they sprout easily, but when they realize it is hot, TURN IT OFF! I guess they only need warmth for sprouting and then back to coolness (I don't have a cooling machine for my seeds, I just bury the pots in the ground under a tree...).

  • YviestevieYviestevie Posts: 7,047

    Not about heat dimwit. Here in the U.K. It's about daylight at the moment. Here's a piccy of my seeds. 


    Hi from Kingswinford in the West Midlands
  • Ooh yay that’s an example of the first setup I mentioned that i couldn’t find a picture of in the wild   image

    (I get that it costs a lot more money to grow under lights which does put people off but I lost everything in a late frost last year so had to buy in my summer bedding plants, which ended up costing me more than the new lights did) 

  • LynLyn Posts: 21,957

    Same here with pansy seeds, germinate late summer, no heat needed, let’s see what happens in the propagator. 

    Have you got lots of room to pot on your seedlings and keep inside until May/June Learning curve. 

    Gardening on the wild, windy west side of Dartmoor. 

  • Any idea when the new serser of Gardeners World is on? 

  • DimWitDimWit Posts: 553

    That's a lot of pansy seedlings, Yviestevie. I've got 30 and don't know where I will place them, you must have a great garden. (By the way, some of my seedlings are purple with the heat, hope they heal).

  • YviestevieYviestevie Posts: 7,047

    Hi Lynne, Ive got a small greenhouse, just keep it frost free.  Seeds should be fine to move into there once they have been potted on and left in the conservatory for a while.

    Not all pansy seeds dimwit, lobelia, pansy, agastache, petunia and lots more.

    Learnincurve, I was lucky found them via amazon (oasis gardening I think).  They were half price so did really well.

    Hi from Kingswinford in the West Midlands
  • Lyn says:
    Have you got lots of room to pot on your seedlings and keep inside until May/June Learning curve. 
    See original post

     Sadly not, the cauliflower will go in the cold frame to grow on which will free up space and there are only a few flower seeds in each of those trays which will be thinned out and probably end up on windowsills when I estimate they are big enough. The next round with sweet peas is the one I actually care about, which will be the pattern - plants that cost a lot to buy rather than normal annuals will be done with hydroponics so I can guarantee they survive. 

    For a large amount of plants rather than seedlings a book case with T5 grow lights hanging down  is the cheapest way but you really do have to be constantly growing a large amount of plants to justify it - 4ft of the quantity of T5s you need for a seed tray’s width costs about £170 and then you get into issues with heat on that scale. 

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