Generally they form on the upper surface of the leaf between the tentacles.
>
>Ok, the reason for including as much of the leaf and petiole (the
>part of leaf which attaches to the stem) as possible is there
>are nutrients and food (starches) in the thicker parts of the
>leaf. These are what keep the cutting going after being removed
>from the parent and feed the new planlets. Also, that's why the
>tips of the leaves died (no food).
In addition, there is less severed leaf tissue to start rotting.
>> The other Drosera cuttings exhibit quite a range. D
>Intermedia seems to grow little plantlets at the end away from
>the stalk. With D Linearis they seem to erupt out of the middle
>of the leaf. With Drosera sp 'Floating, RSA' (Lowrie seed) the
>plantlets grow at the stalk end. By the way, has the latter
>been formally named or identified yet?
Why it that one named floating?
>Nearly all Drosera will grow foliar embyros which, like the name
>indicates, start as little bumps (the embyros) on surface of the
>leaf. The next thing they should do is grow some leaves and
>stem. The roots will have to grow from the stem and at this
>point nearly all the food the parent leaf had will be in the new
>plantlets so this can be the easiest time for them to die. If
>they run out of food before they develop roots... Anyway, you
>can see why it is important to get as much of the leaf as possible,
>and why SuperThive helps (it will help the plants grow roots sooner
>as well as boost the number of plantlets). Petiolaris plants are
>different from other Drosera in that they don't grow foliar
>embyros but need a tiny bit of the stem attached to the leaf
>from which they grow. Perhaps some hormone can be used which
>will promote foliar growth in these plants?
>
>Dave Evans
>
>