MatDz wrote: ↑Tue Jan 26, 2021 6:10 pm
I am following the thread closely as am going to try a similar top layer of sphagnum moss for my Haworthia seeds. Just a comment on the fluffy roots, I am not sure this is what you really want, as later on, when they reach the base substrate, or you will want to start a wet-dry cycle, "regular" roots would need to develop anyway. This is at least what I observed on some cuttings rooted in water and then repotted to the normal substrate.
Good point Mat. However the older seedling has stopped producing those above the moss and has a more typical root structure. I saw similar fine hair roots last year with a perlite: John Innes mix when I sprayed them heavily so I think it is just a reaction to the plentiful availability of water in the sphagnum. (But I got lazy with later seedlings when back at work and I was then less successful with them and started thinking of a new substrate.)
The trick will be whether they continue to do well in it I think! It could be that the vermiculite ones have a slower start but better sustained growth.
edds wrote: ↑Tue Jan 26, 2021 7:19 pm
Good point Mat. However the older seedling has stopped producing those above the moss and has a more typical root structure. I saw similar fine hair roots last year with a perlite: John Innes mix when I sprayed them heavily so I think it is just a reaction to the plentiful availability of water in the sphagnum. (But I got lazy with later seedlings when back at work and I was then less successful with them and started thinking of a new substrate.)
The trick will be whether they continue to do well in it I think! It could be that the vermiculite ones have a slower start but better sustained growth.
That's my observation as well, I am wondering whether those fine roots are then "transformed" to the more sturdy ones, or the seedling will need to grow a completely new ones?
MatDz wrote: ↑Tue Jan 26, 2021 7:31 pm
That's my observation as well, I am wondering whether those fine roots are then "transformed" to the more sturdy ones, or the seedling will need to grow a completely new ones?
The root hairs are cellular projections so don't directly grow into larger roots. As the root gets into the sphagnum then the root hairs will grow more preferably inside the medium and the ones in drier areas will wither.
MatDz wrote: ↑Tue Jan 26, 2021 7:31 pm
That's my observation as well, I am wondering whether those fine roots are then "transformed" to the more sturdy ones, or the seedling will need to grow a completely new ones?
The root hairs are cellular projections so don't directly grow into larger roots. As the root gets into the sphagnum then the root hairs will grow more preferably inside the medium and the ones in drier areas will wither.
So when pricked out they would need to grow brand new roots? This bothers me for quite some time when people recommend rooting cuttings in water, but I newer researched it properly.
It is always worth checking out climate conditions where they grow. Maseru, the capital of Lesotho, has an average max 23C, min 6C in September, which is when rainfall increases and one might expect seed to germinate. So again there is a substantial day/night temperature swing which I believe to be beneficial in germinating seed of many succulents.
MatDz wrote: ↑Tue Jan 26, 2021 7:31 pm
That's my observation as well, I am wondering whether those fine roots are then "transformed" to the more sturdy ones, or the seedling will need to grow a completely new ones?
The root hairs are cellular projections so don't directly grow into larger roots. As the root gets into the sphagnum then the root hairs will grow more preferably inside the medium and the ones in drier areas will wither.
So when pricked out they would need to grow brand new roots? This bothers me for quite some time when people recommend rooting cuttings in water, but I newer researched it properly.
No, there's two different structures going on here. Root hairs are generally tiny projections of the cell wall to increase the surface area for absorption. The larger roots are multi-cellular structures that grow out and these will remain. The fine root hairs will remain if the conditions are to their liking.
Terry S. wrote: ↑Wed Jan 27, 2021 9:18 am
It is always worth checking out climate conditions where they grow. Maseru, the capital of Lesotho, has an average max 23C, min 6C in September, which is when rainfall increases and one might expect seed to germinate. So again there is a substantial day/night temperature swing which I believe to be beneficial in germinating seed of many succulents.
MatDz wrote: ↑Tue Jan 26, 2021 6:10 pm
Just a comment on the fluffy roots, I am not sure this is what you really want, as later on, when they reach the base substrate, or you will want to start a wet-dry cycle, "regular" roots would need to develop anyway.
My take of fluffy roots is that typically:
(a) they develop with newly germinated seeds where the root has not yet made good contact with the substrate, but the humidity is close to 100% so they form a large surface area to either directly absorb water vapour, of for water vapour to condense onto them to be absorbed
(b) they develop on older roots as the substrate is drying out, to suck the residual amounts of water from the substrate
I think provided there is moderate or high moisture availability, "normal" roots, without the fine root hairs, will develop anyway, once roots are in good contact with the substrate.
