Anyone else growing this ?

My plant (planted last autumn) has leaves and flowers, but so far it has
put out no new shoots, and the leaves look a bit on the yellow side.

I can't find any good pictures, so I'm not sure if it needs feeding (it's
had 2 good dressings of horse and chicken manure), if it needs something
else, or if it is just supposed to look like that!

Any tips most welcome.

Victoria
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gardening on a north-facing hill
in South-East Cornwall
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