Bulb lasagne in a trough. Any tips?

[thehousewiththesagegreensofa]

I have just bought a new trough and am working out what to fill it with. It will be at the front and is the only bit of colour there so I want it to look as cheerful and welcoming as possible for as much of the year as possible. Years ago, I was given a "bulb lasagne" kit which had crocus, tulips and something else in which was amazing... until the tulips finished and then the pot just sat there.
Can I do something similar but with dhalias for the summer and then, when I lift them, could I put the spring bulbs in and essentially rotate them?
Any suggestions for what could be in there whilst I'm waiting for the newly planted bulbs or tubers to do their thing?

I have windowboxes with permanent planting of sedum; rosemary; geranium; viola and wallflowers. Atm, the spring bulbs have finished (narcissi, tulip, ipheion, crocus) and I'm waiting on their foliage to die down before I can remove them and then I'll plant out my summer annuals such as cosmos, snapdragon, cornflower, nasturtium and nicotiania. It'll be about 3-4 weeks before they yellow and dessicate so it'll look ugly for this period but I'm willing to wait it out.

Another set of windowboxes with spring bulbs and they'll have bedding geraniums and linaria. These will all flower till November when they die off one by one over the course of the colder weather coming in. I feed them every month to keep them going. Water very regularly and they do so well for me.

You can do the lasagne thing with bulbs in the autumn and plant winter-flowering pansies on top.