Transplant Seedlings

[Moppy]

Hi all, I was looking for people's thoughts...

 

What is the general consensus on when to transplant a seedling. If you have a seed in a 1 inch rockwool block it soon shoots a tap-root out of the bottom. Now, if that were a cutting I would happily wait until the roots are hanging out of the 1 inch before transplanting to 3 inch cube. But, I get a feeling that letting the tap-root carry on down into a 3 inch cube might be beneficial. Anyone got any experience with this? Cheers

[MindSoup]

I don't have experience with rock wool/hydro but I understand how roots work.

When a root tip finds the edge of its medium and is exposed to air (not water or mist) it stops and in turn this encourages other roots to grow and catch up/bush out and travel In other directions as the plant finds it boundaries. Sort of like topping the main growth tip of the above ground plant, if that airspace in front is then filled with more medium/ water/ mist the roots tips will then continue on into it.

So In theory in your situation it wouldn't make a whole load of difference because the same root mass will get the same amount of water/nutrition regardless of its shape but maybe its worth experimenting to see if you notice anything. With auto seeds I would imagine they would prefer your idea as they don't like having as little restriction on their root growth as possible (hence direct sowing into final pot when using soil). In an outdoor setting where the plant is going into ground itself then root mass shape starts to have more of an effect, a thin but long root mass will reach deeper into the soil and thus be less likely to dry out while it attempts to establish itself than a shorter fatter root mass.

[Moppy]

2 hours ago, MindSoup said:

I don't have experience with rock wool/hydro but I understand how roots work.

When a root tip finds the edge of its medium and is exposed to air (not water or mist) it stops and in turn this encourages other roots to grow and catch up/bush out and travel In other directions as the plant finds it boundaries. Sort of like topping the main growth tip of the above ground plant, if that airspace in front is then filled with more medium/ water/ mist the roots tips will then continue on into it.

So In theory in your situation it wouldn't make a whole load of difference because the same root mass will get the same amount of water/nutrition regardless of its shape but maybe its worth experimenting to see if you notice anything. With auto seeds I would imagine they would prefer your idea as they don't like having as little restriction on their root growth as possible (hence direct sowing into final pot when using soil). In an outdoor setting where the plant is going into ground itself then root mass shape starts to have more of an effect, a thin but long root mass will reach deeper into the soil and thus be less likely to dry out while it attempts to establish itself than a shorter fatter root mass.

Thanks for the informative reply. much appreciated and just what I needed.