Wednesday, February 23, 2011

Pistia Stratiotes

Commonly called water cabbage or water lettuce. Why? Their soft thick leaves form a rosette with wavy margins just like a cabbage or lettuce. Too bad its not edible or I would have endless supply of them for salad! It is a genus of aquatic plant in the family of Araceae, found in the tropical, subtropical and warm temperate fresh waterways and ponds.

beautiful green rosettes

The tiny flower is hidden right in the middle of the rosette. Can you see it? No? Well..Im not too sure either if its there because it looks the same to me.....all green colour! Its supposed to bear little green berries after successful fertilisation. But so far I haven't seen them or maybe Im not observing them too closely. The male and female flowers are on the same plant for asexual reproduction. Mother and daughter are connected by stolons which will form dense mats on the water surface.

the roots underneath the rosette

The basket-like shape of the plant traps air bubbles which keep it afloat, while the roots are submerged in the water. Because of the growth habit of the plants, it is considered an invasive weeds clogging and affecting the biodiversity of waterways and ponds in some countries. The dense mats of Pistia block the air-water gas exchange in the water, reducing oxygen and killing fish. They also block light which kill the community of submerged plants.

invasive water cabbage covering my pond
By the end of each week, a thick mat of Pistia will form on my pond, covering almost all surface. I have to throw basketful of them or give out to my siblings and friends who want them, to save my koi. But the plants are also good as they protect small fish and fry under their leaves. They also outcompete with algae for nutrients in the water, thereby preventing the invasion of massive algal blooms.
a single layer Pistia just like the one my blog you can clearly see the tiny round green flower in the middle
the koi also nibbles on the thick soft leaves of Pistia

Pistia Stratiotes in my garden, started with only 5 rosettes given by a cousin, and since then they have multiplied so fast and furious. Other countries considered them as an invasive troublesome weeds, clogging waterways which need to be destroyed. Here, we are clamouring for them as a must-have aquatic plant in our gardens' water feature!


James Missier said...

I really enjoy this plant very much but there is so many setbacks & too much time consuming that finally I had given up on aquatic plants.
These leaves tend to rot giving away a white dusty particles that makes the water dirty & posioned all my little fish. Without the fish - the danger of keeping aquatic plants might breed mosquito's

The best thing I have done is weekly check on each rossettes, keep the medium matured ones which is well formed and throw away the babies and the spend huge ones.

Also - you can trim the roots so that they won't make the pond stuffed with the fiberous roots which might spoil your filter/pump.

I have not seen any flowers nor fruits.I guess you are very lucky to see one.

One said...

You do have a lot of them and they look very healthy. How are your fish doing? I have been having trouble rearing fish. Actually my purpose is to prevent mosquitoes breeding. Maybe the fish know of my intention and are not too happy about it.

Malar said...

My neighbour gave few of them 2 weeks back. This information is very useful for me! Thanks!

Anonymous said...

I really love the color of the water cabbage. It looks so pretty with the koi.

Stephanie said...

I love watching these water lettuce. They are so green and nice. With the sun, they look even nicer :-D I hope they would not cover too much of the pond either. Else your beautiful kois will not be seen hehe...

Happy gardening!

Malay-Kadazan girl said...

You have beautiful pond with cute plants and koi there!My father put the water cabbage in his fish tank sometimes and it grow so fast.

rainfield61 said...

These plants grow and expand and will cover up the pond surface very fast.

p3chandan said...

James I have no problem regarding maintenance of these water cabbages, just throw them in the water.Once a week I will throw some out, no powdery thing, rotten leaves because of the hot sun and nibbled by the koi.As I said, these plants can be useful in containing the algal blooms that might cloud the pond water. You must have a good filter system so that the water will be crystal clear, wash the pond at least 5 months once.

One my fish are healthy though sometimes I forgot to feed them, so they feast on the leaves of water cabbages.I had them since 4 years ago when I built the pond. They have become so big and fat though I still add new fish once a year. If you have a pond, a good filter system is a must for a good supply of oxygen to the fish.

You are most welcome Malar! Dont worry, very low maintenance plant, you dont have to put fertiliser or anything but they grow very fast.

Thank you Donna, I love them when they cover the whole green, soothes the eyes!

kitchen flavours said...

Never realised that they do have flowers! I used to buy these from the nursery and put them in the little pond for the koi to nibble when I'm away for a few days. But lately I'm using cabbage instead, they seem to like cabbage better! Trying to grow these in my little pond is next to impossible, the koi would finish everything in a matter of two days! I gave up! :)

Alistair said...

Looks like just the kind of floating plant that would suit my garden pond, I am not to sure if I have seen this one in our garden centres, it would of course just be seen as an annual plant as it would not survive the winter over here.

p3chandan said...

Steph, because of their rapid growth, once a week I have to throw away some of them so I can see the water surface and my koi too.You too Happy Gardening!

Diana, they really are fast grower but aquarium are smaller so can be easily controlled. But they do look nicer in glass aquarium, can really see their roots below the water,and fish love to congregate under the leaves to nibble on them.

Rainfield they grow fast and furious but have to manually throw them away!

Joy, their flowers are actually like a very tiny green buds right in the centre of the rosette. Real cabbage? Expensive lor to feed your fish, I give pellets only. To protect your water cabbage from the fish, put a few of them in a pot without holes, same height as the water surface. So that the plants stay in the pot and not moving about in the pond.That is what I do to protect my water hyacinth which my koi love because of the soft bulbous stems.Try it!

Alistair, yes I guess these wont survive your cold climate but you will enjoy seeing them floating in your pond for the rest of the seasons!

Lesley said...

I would definitely eat the pistia if they were edible! But I go the other way too...I wanted to fashion my last edible head of lettuce into a bridal bouquet.

~Holly~ said...

Ohhh they're very lovely!

TheFusionTea said...

The leaves bloom like flowers. Fresh looking.

PlantPostings said...

Amazing plant, and I love your close-up shots with the droplets of water. Beautiful!

p3chandan said...

Hi Lesley, the rosette of the water lettuce or water cabbage looks exactly like your lettuce bouquet, and edible too!

Thank you Holly.

Thanks Fyrul for visiting my garden.

Thank you Beth, usually I took photographs after I water my plants!

milka said...

Yo.... p3chandan! Your pond is so beautiful, got Koi sumore! Wah. Do you always sit there and day dream?

p3chandan said...

Yo Milka..thank you. Of course la..always sit at my pondok next to it and daydreams!:)