did you say it was painted? or is a proper ceramic glaze.?
There is no reason for the shape to have an effect.
is it stod in a very hot space or particularly cold space? these are the most common causes after poor watering and vine weevil grubs eating the roots.

Are there any grubs in the compost around the roots Nariz?

sorry lots of questions.

The other problem might be the size - it holds a lot of compost, and there's a chance any plant put it in will suffer from souring of the soil - very little root to soil ratio. Pots shaped this way are difficult to plant - anything permanent put in there which will reach any size will eventually mean your having to break the pot to get the plant out when it needs repotting or disposing off.
I'd be inclined to fill it up with broken slabs or something to keep it weighted, and find a pot that's just the right size to sit inside the top, and plant into that instead.

I agree with Bamboo - it is really hard to get anything mature out of a pot that shape, although it is very pleasing to look at. I would also, as B suggests, sit a pot inside it. That way the pot remains admired but you can change your mind from season to season as to what goes unto it.

it looks glazed to me as apozed to painted . having done pottery i know some glazes have nasty oxides in them and heavy metals . i learned the hard way putting glazed stuff in my tank which slowly but surley killed my plecostamus fish .

Is it in fact ceramic or is it concrete - as you say its heavy I wondered. I have a concrete planter that seemed to kill off whatever I planted for a long time. I just have a fern in it now and its OK, but it must be 10 years old so if it was giving out anything toxic perhaps its all gone by now. I did go down the route of sinking pots in it before I finally put the fern in.

Try lining it with black polythene (with a hole in the bottom)for a season and planting annuals to see if it makes any difference.

I'm assuming the pot has a drainage hole?

But its such a lovely pot it would make a nice decoration in its own right.

Yes, I agree, it is gorgeous in its own right. I had an ali baba pot just stood at the end of a narrow path with nothing in it at all, looked great. Broke it though...

I have a ginko tree in one and i know there will come a tie when it will have to be broken......

Probably years though, Seaburngirl - they're so slow growing anyway.

thats why I put in into this large pot. it will probably outlast me :o)

Just a thought.... but do you put anything under the pot to keep the pot slightly raised off the ground like a plant stand of some sort. I have many pots in my garden and under everyone of them I have under them something obscure underneath them. I first done this as the pots were making my decking rotten underneath and then I discovered that it helped with the plant drainage.

It looks like a standard glazed, high-fired, Indonesian earthenware pot to me, Nariz. It's much like many of those that we sell at work. As a 10 inch deep pot, it isn't even very large, as that type goes. Note that garden professionals have found that drainage crocks actually have the opposite effect, and a piece of plastic window screen, or counted cross-stitch screen over the drainage hole seems to work better. Also, moderately sized as it is, starting a single small plug plant in a pot that size will leave room for the soil to sour, as Moon_grower says. I would double-check the kinds of plants that you have been trying, and the kinds of compost that you have been using in this pot--ivy geranium likes a coarse, fast-draining, gritty compost. If at some point the pot had been disinfected with the wrong solution--such as chlorine bleach--that could have adsorbed into the clay, and bother plants for years thereafter.

Ooooh! Lots of ideas to go with! The pot - judging by its bottom - is definitely terracotta and, not knowing anything about glazing pots, I would assume that, due to the heaviness/size ratio, Tugbrethil, Noseypotter and Steragram are probably right. It does have a drainage hole but a rather small one; I haven't ever stood it on 'pot feet' or stones to aid drainage (duuuurrr!) and I have always put plug plants in it in universal compost which - as Bamboo rightly states - with very little rooting probably made the compost go sour (another duuuurrrr!). So - there we have it!
Note to self: Just because you fall in love with a pot doesn't make it a good planter! From now on I shall use it purely as decoration or, if I have something in a pot small enough, will stand it inside.
I'm so glad I found this site - even after 4/5 years you are all teaching me stuff! Thanks guys. :o)

if you can drop it in a bigger container of water to soak possible toxins out that may well help thow i agree the shape isnt ideal . perhaps try a nice mint in it as that needs to be kept on its own and seams to grow anywear ? you could use it as a water feacture with one of those black plastic tubs you bury with wire on top . put pebblles on top to hide the pump then run a tube in the bottem with some cylicone and use bigger natural stone to hold it at about 45 degrees . just a thaught .

You are so full of great ideas NP - that would look great. A solar pump would be the finishing touch.

sounds good sterogram nice sound of trickling water .

Mmm - running water's a great sound, but I think I've found a solution that suits me .... I'll fill it to half way with stones and pop a small pot with a newly rooted rosette of Sempervivum in the top. That shouldn't cause any 'sick' problems; will give the Sempervivum great drainage and will also make the pot look 'used' rather than just decoration. Thanks for your suggestions guys. :o)

your welcome sounds good .