Problem with Gunnera Manicata.

I have a plant which was sold to me as Gunera Manicata. It stands beside the pond in a large hole lined with plastic to keep its feet wet.

The coming spring will be its 6th so by now I should be expecting large tall leaves, but so far it has been disapointing, growing to about two feet with leaves about two feet each. The root ball when I dug it up to insert the plastic liner weighed nearly 200 lbs, and it has about 15 flower spikes. It has also produced two seedlings which have grown to about the same size.

I'm wondering if one of two factors could be true.

1. It is short of nitrogen, the dark green leaves would indicate to me that this is perhaps not the case.

2. It is not manicata. I'm wondering if there are smaller gunneras which look like manicata in everything but size.

Can anyone help please?

 

Could it be the plastic liner thats the problem Rich. As you know these get massive and you are in effect growing it in a container.
There is another Gunnera, tinctoria thats a possible candidate.

 

there's a gunnera magellanica whih gets to 1" tall and 12" spread!!

 

I put the plastic in last winter. The hole is about 6' across and 5' deep.

magellanica looks too small even for my pathetic specimen.

Here is a picture taken last August. The gunnera is in the foreground.

 

The leaves do look a bit short for August, I take that it can get at the pond moisture.
If the liner can hold moisture then it might also restrict moisture in a dry summer. Just a thought.

 

Looking again at the picture, it looks like at least three crowns, when you consider what your expecting from the plant, maybe a 6 ft by 5 ft deep hole isn't really enough, big that it is.

 

Tow of the crowns are outside of the liner, they are the seedlings which were produced. The main plant is the rightmost one

 

This is the lines hole, january, 2005

 

How do you keep it topped up Rich, bearing in mind these grow best when completely saturated.
They are nice looking seedlings.
I presume your pond has a liner, if so, I reckon those seedlings will be rooting under that liner, and they might do better eventually than the original.
Trouble is they might puncture the liner or at least deform it.
I think its a moisture problem, not getting enough.

 

Last yeat I watered it every day. I take the point on the lack of water, but feel that even with that problem it should grow somewhat bigger than it is.

It's a real frustration for me.

 

Rich
Your 1st photo doesn't look prickly enough to be Manicata. I have one that grew bigger than that when it was in a tub. There are smaller ones, they have one in a glade at Angelsey Abbey, but what they are named I don't know.
Silly question, but why are you lining the hole?
Nik

 

I thought the small size may be due to lack of moisture around the roots. They are pretty spiney.

 

I think when you line a hole such as this, in order to create a bog garden, its normal for the pond water level to be able to top up the lined hole.
The idea is that way the lined area stays very wet, can mean that the pond has to be topped up regularily though

 

Gosh, I'm with Pete again.
Rich, could you put a pipe between the pond and the lined Gunnera pit, 1.5" waste pipe would do it.

Nik

[ 19. February 2006, 09:11 PM: Message edited by: Nik ]

 

Rich
I've just noticed your location.
There are some very big gunneras by the side of the road into Brighton from the north.

Nik