Should I go big , or go risky?

The front section of the main succulent rockery is finished and stepping back it was good to see what gaps are left for bigger plants.  There are 3 or 4 nice spaces along the front ready for one of the agaves or other feature pants.

Looking at the available agaves raised the two issues I have been avoiding: do I risk the marginal, or favourite plants and how much space to allow for the future.

This agave parrasana fits perfectly next to the a. parryi group. 

There is a much smaller one planted elsewhere, but I am not sure I want to risk this one.  They have scrapped through in my old dry bed, but with damage and never really thrived. I suspect this is due to the small size of previous plants, but the only way to find out for sure is to plant this larger one. Do I risk it?

Another space is perfect for this agave franzonsinii

The colour is great and the plant has room to grow to around 1m.  Seems fine until you check on the stats and find that they can grow to 3m. Even 2m would swamp that location.

Maybe the agave mitis albicans would be a good substitute.

Much better size wise, but I've never seen one of these tested for hardiness. The normal form is fine for me, but white versions of plants never seem to do as well.  Besides such a nice plant and hard to get hold of, is it worth the risk?

Agave weberi latifolia then.

Apparently around 2m this one, which is on the large size. Plus it is the wide leaf version which is such a good plant. This one manages to fit into both categories.

From the wide leaf to the narrow, agave utahensis

The size is good, and it can take cold if kept bone dry.  I wonder if a cloche would be dry enough given it would be grown in almost pure gravel. It is so slow though, any damage really would take for ever to grow out. Probably not worth the risk.

Agave 'Cream Spike' would look great planted, especially as it is getting to a decent size now.  I think the plant has now been moved from agave parryi to agave applanata. They have been talking about it for ages.

No one in the Uk plants these out. It has been fine in the cold frame and even just left under rain covers in a pot, but again there is something final about planting it.  Does anyone know how these would cope?

I do have two agave gentryi waiting to go somewhere. This is the larger of the two.

No problem with hardiness if protected from the worst of any snow.  Again they can get really big, but I am guessing here would probably settle at around 2m. The other one is much smaller currently and is the 'Jaws' form with nice big gums and teeth.  I think I'll keep that one in a pot as a feature.

Apart from the immediate problem of finding plants to fill the gaps, it is going to make for a very interesting garden in 10 - 15 years time.  On top of large plants here, there are the 4 agave montanas, 2 agave salmianas, and a few variegated agave americanas. That is a lot of agave for a small garden, but when do we ever really think about the ultimate size our plants could get to.

While I decide, some of the remaining pots have been used to fill the gaps.

 

Moving the pots has freed up the old storage area for the next stage.

This is the area earmarked for more lush planting. Up until now the plants have been spred out and all succulents. The cycad on the left of this photo marks the start of the shift, the idea is to start mixing in other plants and for the everything to be packed together. I am guessing that most of the large agaves from this post will end up in here fighting it out with other plants in my version of a jungle.

But back to the immediate issue, do I risk my prized plants that wont outgrow the spaces, or plant the big ones and either move them later or worry about the overcrowding when it becomes an issue?