Should seed trays be dark?

[fran]

Morning all!

Just realised I posted this first on wrong forum. Sorry! Well - what I wld like to know is if I use clear plastic food trays for germinating seeds, should they be lined with something dark? Does it matter if the roots glimpse a bit of daylight?

Thank youoooo

[HeyWayne]

I thought they were dark to encourage heat. Something black left in the sunshine will likely heat up more readily than something white after all.

[fran]

Mm. Yes - thanks Wayne - but do roots try and grow away from light i.e. would transparent seed trays prevent them germinating properly - or, as the seedlings are only in there for a couple of weeks (hopefully!) - it doesn't matter, light or dark?

[janeyo]

I've had caulis and broc sprout in seethrough trays quite happily. I would give it a go and see what happens.

janeyo

[ClayGarden]

I've just plonked my seeds on top anyway rather than even covered in the compost and there on the window sill so they've hours of direct sunlight for days now, and they've germinated in just a few days. The roots also gone down into the compost, so they know which way to go even with light.

[fran]

Sorted it! If necc, I'll just cut up a dark plastic bag and tape it round the bottom!

I'm sowing some leek seeds and painstakingly trying to space them 2 cms apart. Am I being daft?

[Farmer_Gyles]

daft? no
but you may be worrying too much and/or making more work for yourself than necessary

[HeyWayne]

I would suggest that roots search out nutrients, so as long as they're covered in compost, they should be fine whatever the container.

[Matt.]

Light won't go through the soil. I think wrapping in a black bag is a lot of effort but its your time and it may yeild some benefit. I'd just do the quick and easy approach.

[ClayGarden]

I agree about the light wont go through the soil. Just put compost in a freezer bag and old up to the light, you wont see anything but maybe the odd shard of light.

[Snadger]

I have used white plastic cups from a vending machine before for plants but they get green mold forming on the sides due to the soil being exposed to light. Same with early potatoes where I used white containers instead of black and finished up with green taters which are poisonous to eat!
Containers made from dark materials are always better for growing plants as logically we are trying to mimmick soil conditions and we don't get light to the roots in mother earth!

[bluemoon]

Perhaps you could use something more conventional for the compost and use the see through things as mini propagators. I wouldn't think that using them briefly to raise seedlings would hurt though.

[Eyren]

If I remember my biology lessons correctly, roots are geotropic, i.e. they are sensitive to gravity and will always try to grow downwards. It's only the shoots that are phototropic, i.e. they grow towards the light.

[Topaz]

found this thread very interesting as i work in a supermarket and have an abundance of trays that youghurts are delivered in. Use them mostly to sit plant pots in as drip trays but have just planted romanesca in them and they have germinated with no problem at all, I say go for it.