Potting Eryngium

Want to pot my Eryngium planum in this container and want it to stay there for a couple of years, if not permanently (planning to remove old wallflowers first of course, LOL). Wondering what soil mix would be ideal? I have John Innes 3, sharp sand, coarse grit, MPC and garden soil (heavy clay). Container is about a foot in diameter and depth.



Thanks,

Nick

 

Eryngium preform best in very free draining soil, ideally poor soil they say you get more intense colours , full sun. So JInnes 1 or 2 with sand/grit with a mix of compost . It will happy grow in any soil you find as long as its not to rich and it free draining, I wouldn't go rushing out to buy JInnes 1 or 2 if you haven't got any.

I've grown planum before its a poor relation to other variety's , its very leggy with small flowers .

 

Thanks @Perki! Perhaps then 20% of each with sand/grit, and 60% multipurpose compost?

Nick

 

Maybe 20% garden soil - 40% -50% M compost the rest grit or sand or both.

 

Thanks again Perki, yes, probably adding some garden soil is better to retain moisture.

Nick

 

Nick, I don’t think it is really a container plant. Why do you want to grow it in a container? Planum forms a long rap root and once planted should not be moved again in my experience. Plant it and leave it! Transplant it or move it and it usually dies
Another reason for not growing it in a container is that it’s prickly...of course....and containers are usually placed where they can be touched.
Here a group are grown in very poor, sandy and impoverished soil in full sun ..never fed and never watered.
Agree with Perki that planum generally are not the showiest of eryngiums except for Jade Frost, a beauty. For example, x Z. Big Blue really is a show stopper.....very tall and very blue

 

Because I would probably struggle to get it to grow in my heavy clay Verdun, especially in the back garden where there is a lot of shade. OK, perhaps a better choice for this container would be Salvia 'Blue Marvel'. Now, what about the soil mix required for that one? And surely the Eryngium still needs to go into a slightly larger pot until I decide where to plant it if it can't be transplanted later when mature.

Nick

 

Hi Nick, what about planting it in a deep builders bucket ( 95p from B&Q ) and sinking it into the ground. Then you can control the growing medium.

 

Thanks @KFF, I don't like the thought of growing things in containers in the ground but perhaps I'm just being idealistic, that might be a good idea. Certainly worth considering doing this with some plants!

Nick

 

Ok, makes sense Nick
Yes Blue Marvel would be better choice....can be divided too when bigger. Well drained soil....I suggest John innes and add some grit and I like to add just a little dried manure or chicken pellets.

Re the eryngium....it will grow for a year or so potted. I did that here whilst I waited for the right garden spot. It can be repotted rather than transplanted. If you can find a nice warm or hot spot in the garden can you make a suitable soil using plenty of grit?

 

Which John Innes mix for the salvia please, Verdun? Yes, I plan on starting a new border next to an outhouse wall, nice and hot and quite sunny for it and not too 'boggy', like the area lower down there. Adding plenty of grit to a large area and digging over a fair bit seems to work better than focusing on individual plants, then I can add some sand for the eryngium.

I enjoy the challenge of making the soil suitable for incompatible plants, despite all my failures over the years.

Incidentally, where do I get the dried manure and chicken pellets from?

Nick

 

Oh, you meant number 3 Verdun, sorry. My brain seems to take a while before getting going in the mornings! (isn't great at the best of times!)

 

The planning stage for me is an exciting part of garden design Nick.....
Yes, preparing the whole bed and aiming then for suitable plants that will thrive in those conditions is the way to go
Not just colour but shape and form too using contrasting or complementary plantings.
On paper, I make sketches, analyse, change my mind, move things etc., over the autumn and winter until I finally settle on the scheme.

Chicken pellets? Places like poundstretcher, B & M, etc., etc., sell this....possibly on offer at this time of year. Ditto dried manure ......can be animal or plant derived .....available in bags.