Floating gardens, simple hydroponics with living soil for difficult plants

[Tristan_He]

Axel this is a really interesting thread, please keep us updated.

Floating fen and bogs are widespread in nature so I suppose we shouldn't be surprised that this works. If I can think of somewhere in the garden to put one, I'll give it a try.

Best wishes from Wales.

Tristan

[partisangardener]

One of the advantages of this method, it doesn't require a long term space of a garden from the beginning,a empty water bucket is swiftly moved. Comparative little work and little care needed, compared to a regular seedbed in the garden.

A friend urged me to sow on these islands Pulsatilla occidentalis which is probably a bit difficult.
Apart from some orchids I disseminated these and some Gladiolus palustris, Primula maximowiczii and a lot of other plants.

Each different raft has only a few seeds of each species because different mycorrhiza is to be expected. Transplanting is very easy. The soil is very fluffy. Anything I pick up will grow on without pause on another raft.
This is my experience as far.

[partisangardener]

If I succeed I just give him some of these floating seed beds.

My next goal is to make rafts out of empty plastic bottles. Grown in they should look as natural as the other ones.
Much more accessible than hard Styrofoam.

[partisangardener]

Some plants need more light and a cooler habitat.
My first bog arrangement has only 6 hours sunshine In the afternoon until evening there is only shadow from the house.
So it keeps quite cool through natural  evaporation. A mirror background provides enough light, and doubles the scenery.

Now it is two years old and I can harvest moss and other plants for the new rafts.

[partisangardener]

Total of the first floating bog arrangement. The piece of Styrofoam in front is for my knee.

[brianw]

Hi again
Am I correct in assuming the absorbent fabric/fleece, apart from being used as a "wick", is only used to hold the pots onto the flotation material? It does of course also provide a growing base and background for mosses etc, outside of the pot itself. I could also just wire the pot to the float, for practical purposes. I have found a source of the fleece fabric in a local dress fabric shop; ~£8 a metre, 1.5 metres wide. In green (and many other colours) of course ;-)

Merry Christmas to all, Brian

[partisangardener]

There are no pots or suchlike in this system. All (really all) plants grow on the flat surface of the floating Styrofoam above the waterline. That is what supplies the optimum growing conditions and the high oxygen level at the roots.
To cut holes into Styrofoam to insert pots is not nearly as good.

For a starter the colour is a bonus. But moss and the plants will cover whatever its colour is.
The starter thing on my first post, has apart from moss some peat on it. When I had to sow some seeds, I just pushed some of the moss aside, added some peat and the seeds on top. No pots needed a natural growing hummock.

[partisangardener]

I started some seed beds with sparsely some sand grains on top. Germination was very good, even some Orchid germinated there. For mycorrhizal fungus I spread some living roots of Erica on top.
https://www.srgc.org.uk/forum/index.php?topic=18290.0
After the second season I put this late autumn some peat on top, Growth was not sufficient in my opinion. Especially Gentiana seedlings grew very slow.

But Drosophyllum was going quite strong without any substrate apart from the fleece. It was very hungry at the beginning, so I placed the whole thing outside and the little natural food there kept it going.

[partisangardener]

At the moment I experiment with alternative rafts. Lots of empty plastic containers pollute our environment and are easy to access. (Here in Germany not that easy)
My idea is to put them into a synthetic pillowcase and put the fleece and some substrate on top. The moss and other plant cover will protect it of UV ray degradation and these floats could accumulate lots of CO2 while they last and look good too.

[partisangardener]

Bog plants in pots, often have problems with anaerobic degradation in lower parts of the container.

The oxygen-free zone in a natural bog is usually much further down than in our containers.
To keep the oxygenated state in your substrate I can offer several more solutions.

You could use containers with grill structure (I do not know the term in English) to ventilate the substrate.

You could use some mesh-bag as a container. I experiment at the moment with cut off legs of old trousers, stitched up at one end.
They probably tend to be overgrown by mosses and will hopefully look quite natural then. Synthetic material will last longer. Moss will shield it from UV-ray.

Addition of structure matter like heather twigs helps too for aeration in these situations. Live Sphagnum in strands up to the surface works on the long run too (heads up of course). Only in the bottom half it works for a limited time, because it disintegrates soon and looses structure.

Long dead strands of Polytrichum ssp. moss work for a very long time. They are very resistant and provide ventilation for a long time.
They work quite good for me alive, but you end up soon with a clump you cant divide without a chainsaw or a laser beam.

I have just started a list (not complete yet) what species grow there on my floating gardens.
 Helonias bullata

Helonopsis orientalis (breviscapa)

 

Cypripedium tibeticum (low ph)
Cypripedium reginae   (medium to low ph)
Cypripedium acaule * (very low ph)

Pogonia ophiglossoides
Epipactis palustris seedgrown there in acid ph
Dactylorhiza praetermissa (neutral ph)


Polygala paucifolia*+seeds

 

Drosera binata
Drosera anglica
Drosera intermedia

Drosera rotundifolia

Drosera tokaiensis
Drosera filiformis
Drosera linearis*+seeds

 

Pinguicula grandiflora

Pinguicula vulgaris


Sarracenia alata
Sarracenia rubra

Sarracenia purpurea dwarf form
Sarracenia leucophylla seedgrown and plants from BG Prag
Darlingtonia californica mountain population Oregon seed grown

 

Chamaedaphne calyculata nana  seedling
Andromeda polyfolia
Vaccinium vitis-idaea
Vaccinium myrtillus
Vaccinium uliginosum

Ocalis acetosella

 

Iris chrysographes seed grown black form
Iris setosa
Mentha requienii (weedy)grows extremely well, very hardy there but overgrows everything
Fritillaria meleagris
Fritillaria camtschatica grows very well, pretty low plants without ferilizing

Erythronium dens-canis

Narthecium ossifragum

Polygonatum hookeri (dwarf)
Primula integrifolia
Primula matthioli

Primula rosea



Soldanella hybrid

Gentiana acaulis
Gentiana pneumonanthe

 

Trillium grandiflorum

 

Selaginella involvens

Adiantum raddianum (high and low Ph)

Gymnocarpium dryopteris

 

[partisangardener]

Pictures from the construction site

[partisangardener]

At the moment I experiment with alternative rafts. Lots of empty plastic containers pollute our environment and are easy to access. (Here in Germany not that easy)
My idea is to put them into a synthetic pillowcase and put the fleece and some substrate on top. The moss and other plant cover will protect it of UV ray degradation and these floats could accumulate lots of CO2 while they last and look good too.

One pillow case is already filled with some Coca Cola bottles and some waterbottels both plastic and already covered with some moss. Alas snow is on top, so no picture. The next set is already waiting. I let it float in another pillowcase, to see how they take heavy weather.

Possible that I get more of a similar size until spring. Maybe a simple solution for capturing excessive CO2 out of the atmosphere lies in the plastic garbage we already have.

[partisangardener]

Because it was asked for, I have an update to explain some of my systems in more detail.

The first islands were frameless or with flat Styrodur sections (2-3 mm attached with toothpicks, except for the right Cypripedium thibeticum part, which has a 15 cm frame, which I glued with construction glue and stabilized with bamboo skewers (rods from garden bamboo).

For the rain barrel part and some others I only put moss cushion parts on it. When I had to sow something, I pushed the moss aside and applied substrate and seeded it there.

 

Most of the frame parts are narrow sections and really only necessary when they are outside and there is a risk that a heavy rain will wash everything away before it has stabilized.

 

If you have enough moss cushions, you can simply make a frame out of it at the edge and fix it with toothpicks. They then catch washed-off seeds etc. and also grow relative quickly with their rhizoids. I still do these and it seems to work well.

 

Sphagnum works quite well as a cushion (even if it has no rhizoids), but if you want to settle individual moss threads you can also tap in half a toothpick at short intervals and then weave the moss in. I cut  curtain rods plastic packing into strips.

But I found the idea with the toothpicks better when I thought of it because I couldn't get hold of those transparent plastic strips anymore.

 

Covering the whole system with acrylic glass plates against heavy rain are too unwieldy in the long run with the amount I have and they would also be expensive if you don't get a few sections for free like I did.

So I also cut with 2cm Styrodur-plate strips and framed these seadplates afterwards. So that the seeds are not washed away.

 

That works too. Only the Drosophyllum has died because I probably pinched off roots with the flat edge strips (it was on the edge). I'll start some new again soon.

 

Now I lay out short pieces of toothpicks at intervals of 5-10 cm before I install edge strips made of Styrodur.

 

A good but slow-growing moss for the border is Riccia fluitans.

[Véronique Macrelle]

since i read you, i have been looking for suitable polystyrene pieces, but they are less and less used (and so much the better for the planet, no doubt).
I also have this problem that the water holes in my garden dry up every summer almost now and I have completely lost my sphagnum moss and the plants that went with it.
maybe this is a solution for some plants:what minimum raft size did you make?
I found a small piece of styrofoam about 15 cm in diameter...

[partisangardener]

15 cm is quite ok. Maybe cushions filled with plastic bottles are more suitable for you.