How to trim....

[Christian Walker]

OK so I have just finished planting over the course of about a week. the early plants are already growing. I have a thin layer of Tropica plant growth substrate under unipac sand (in hindsight I would have used more of the Tropica at the back as its banked up a fair bit). Im using AE nitro liquid carbon and not adding ferts yet. Lighting is 2 x 39W T5's over about 2OOL of water.

Question is about the right way to trim / propagate. I will list what plants I have and if anyone can quote and annotate under each one, the best way to take cuttings I would be grateful. Ive always been unsure of whether to trim stems at the bottom or midpoint or top etc... and whether you get two new stems sprouting from where you cut etc. So here is the list and I welcome any help you can suggest....

1. Polygonum sp sao paolo <started turning pink which I'm pleased to see>

2. Hygrophila polysperma

3. Hygrophila pinnatafida

4. Various Cryptocorynes

5. Pogostemon stellata

6. Vallisneria nana

7. Ludwigia repens rubin

8. Sagittaria subulata

9. Ammania sp bonsai

10. Aponogeton boivanus

11. Alternanthera sp rosanervig

 

[Mick.Dk]

1,2,(3),5,7,9,11 are stem plants. If plants are in good health, cut as low as you possibly can - preferably leaving a few leaves on the "stub", left behind. From the cut-off parts, cut into desired length and remove lowest pair (or two) of leaves. Re-plant amount of those off-cuts, you desire, either among the group you trimmed or somewhere new (or both). The plants you mention are very willing to root from off-cuts and to produce new growth from the "stubs" left behind.
Hyg. pinn. (3) is a little different. When you cut up-right stems, it usually produces more horizontal growth, which most find desirable. At some point the plant will again attempt vertical growth, though - same procedure will bring horizontal growth back.

 

[Mick.Dk]

Crypts. are rosette plants. Their reproduction are a little different, in that some send out root-runners far away, and some keep their offspring close to mother-plant. The latter goes for C. wendtii- types (by far the most common ones), and those need to be pulled up gently from substrate, as they grow too dense. The "tuft" is then gently divided by pulling single rosettes (plants) apart and re-plant separately ex. in a group.
The first category is morexeasy, since you just gently pull out offspring as they appear, making sure you disconnect before pulling mother up, too. Re-plant offspring at desired, new location.
P.S. most Crypts. do really NOT like to be moved to another type of water-conditions (anothervtank). They will often loose all leaves ("Cryptocoryne melt"). Usually new, adapted leaves will appear within some weeks, though, and plant has adapted.

 

[Mick.Dk]

Vallisneria and Sagittaria you will soon discover, reproduce by runners. New plants appear along those runners - like Strawberry-plants does. The "string" connecting the plantlets can be broken, and plantlets re-planted individually.
Usually they go everywhere, by themselves, though - so trimming away is needed.

 

[Mick.Dk]

Aponogeton boivianus is a bulb-plant (or a tuber,actually - but same/same). If plant is very healthy, well-growing and thereby LARGE, it is possible to very carefully cut and divide the tuber. Both pieces need a growing-point (not allways visible), to produce a new plant.
- I would not recommend trying, unless absolutely necessary, since chances of both parts rotting away after, is very high ( it's waaayyy safer to buy a second one - if anyone really think they can house two of those giants !!)

 

[Christian Walker]

Thanks Mick.Dk what a thorough reply. You have set my mind at rest a bit too. Just one question... i think i know the answer but if I cut a stem low down, will the already planted section grow two new stems from where it was cut ?

 

[stu_]

Yes.
2 new stems will grow from the highest node left on the original stem.
Any of the original stem/stalk left above this point will die back and look ugly imo.
Therefore I like to trim stems back to as close to a leaf node as possible.That's not always easy though if it's a big clump.

 

[Christian Walker]

Great thanks. Plants only been in a week or so and growing great. I can see the need to trim soon !

 

[Mick.Dk]

Just to clarify;
amount of new stems growing from cut stems will vary according to plant species, and general health/strength of plant. Therefore it is really not possible to "predict" how many stems will appear.
Ex. Rotala rotundifolia is VERY good at producing multiple stems from cut stems- whereas Rotala macrandra is generally quite poor at it. This in conclusion mean, that it is advisable to re-plant many cuttings from Rot. mac. back in the original group, to get lush and dense group. Usually re-planting Rot. rot. in original group is not necessary, since multible branching will produce the density.