I do. The seeds of Sedum are incredibly tiny. They ideally should be sown in Spring. and they do take a fair while to get to a decent size plant. Better idea would be to find someone with a patch of Sedum and beg a lot of pieces. They root easily.
Viburnum beetles. Spray with a good insecticide and keep spraying. Try to remove any leaves with pupae on them too.
Very carefully remove the pink flowering branches at the point of origin, leaving no stump or they will regrow just as vigorously.
In all the years I have been looking at wild flowers in various parts of England and Wales, I have never seen an Alder Buckthorn, either in flower or in berry. Looking at the images though it would be hard to mix them up with Blackthorn (Sloe).
They need the leaves to feed the bulb so I would not recommend cutting them off. All I would do is to top up the pot with compost. The bulbs will not care about being buried deeper. In fact they probably will do better. Then plant your pansies over the top as before.
This is a plant once, weed out forever plant, do be warned, it seeds all over the place. Don't understand why it is so expensive in the Garden Centres either when it is so easy to grow.
Those are Damsons, or possibly a wild plum/Bullace. Certainly not a sloe. Usable in alcohol either way.
To keep the envelope and contents flat so that it does not exceed the thickness limit by bunching together, I use a tiny piece of double sided tape to hold the seed envelopes in place inside the posting envelope.
Important thing to do though is to remove all the plums, when ripe and burn or bin the infected ones. That reduces the population a little.
Transplant when young, they hate root disturbance and more often than not die if moved when bigger plants.