What to plant in the garden now for summer?

After the fiasco that was last 'summer' (only the calendar looked like summer, for me spring went straight to autumn)...
Anyway, I never got around to doing any spring planting at the end of last year, but happily the previous years daffs, snow drops and crocus are battling their way out as I type.
Can anyone recommend a few flowers to be planting now, I'd like some big blousey flowers maybe with some scent, and nice and bright....
With the nice weather at the moment (ie no rain), i'd like to do a tidy up this weekend, and maybe plant out a few things after i excavate the weeds from the beds.
The garden is only 2 years old, so I'm open to any suggestions... Soil type is clay, and tendency to hold water when we have a summer like last year...

If it's flowers you're interested in, then i'd say check out your local Lidl if there is one near you. All their summer bulbs are available since this morning, lots of different types of flowers including lillies, gladioli, dahlias - lots of colour and scent, and at only €3 per pack of bulbs, you can't go wrong.

If you want flowers this year you should be getting many seeds into the seedtrays in warm cupboards NOW! Some bulbs flower in the first year but read the packets/do the research. If you want veggies and fruit they should be started shortly.