Do not exclude light

To reduce legginess, I keep my tomato seedlings as close to the light as possible (2 x 4ft Cool White fluorescent tubes).
These tomatoes were sown on Feb 7th and transplanted to 3" pots as soon as they were large enough to handle. My propagator is a plywood box 4' 6" long x 22" high x 18" deep. The heat source is a 65watt Bio Green Heat Matt under a 30mm layer of sand.

Kevin

 

I'm intrigued by this. I'm assuming the lights are not proper grow lights, but rather just ordinary domestic flourescent strip lights. Is that right?

I've been mulling over the idea of making something in my spare back room, but have been put off by the cost of proper grow lights. If you can achieve the same result from ordinary lights, I'd be up for that.

 

:thumb: Its the old "inverse square law"- double the distance from the Lamps and the "power" of the light goes down by 4x. Fluorescent tubes should be within an inch or two of the leaves (so long as they are not generating enough heat to burn the leave).

"These tomatoes were sown on Feb 7th"

They look very good, and stocky. They wil be fruiting LONG before everyone elses' :thumb:

"The heat source is a 65watt Bio Green Heat Matt under a 30mm layer of sand."

What's the blue/green plastic thingie I can see?

Have you got a sandwich?

Plastic (that I can see in the photo)
Sand
Heating mat

perhaps?

 

The ordinary domestic or office cool white fluorescents work extremely well in a propagator where you are just raising plants from seedlings to the point where you will be putting them outside (eg tomatoes etc). The more expensive full spectrum or grow lights are only required if you are keeping plants inside permanently to flowering and fruiting stage.

Making up a propagator is only a a couple of hours work and the only real expense is a thermostatically controlled heat mat (mine cost £60).

Kevin

 

I was thinking it would be cool to build an arrangement such as yours, and start perennial flowers from seed in late autumn/early winter, ready to go outside (with some protection) early in the following spring, so that they are ready to bloom all summer.

 

The blue/green plastic thingie behind is just a max/min thermometer. The blue/green base the pots are standing on is an old windowsill propagator - which no longer works - just something to stand the pots on.

The base of the box has is insulated with 1" Polystyrene sheet followed by a Layer of aluminium foil followed by the Bio Green Heat mat - another layer foil and then the 30mm of sand.
The sand distributes the heat nicely and soaks up spillage.

Kevin

 

The "problem" will be if you don't already have the fittings lying around. The tube holders, and ballast, are not very cheap, and you need a lot of lights. I've tried with just one above the seedlings in my windowsill propagator and it made absolutely no difference that I could detect. You may also need a "contactor" (or whatever it is called) for the Timer as the startup current for a bank of fluorescent tubes may fry and ordinary timer (but not my field of expertise so I'm not sure; I am sure that I need one for my 400W Metal Halide growing light )

If you've got an idle hour or two have a wander round the a Cannabis forum, they have the whole light thing down to a fine art. There is plenty of info about how many tubes, how much light they put out, and so on. They are fanatical about their plants, and as such you won't need equipment that matches that!!, but the data you will find will give you a good basis for a reliable substitute I reckon :thumb: