Deadheading prevents the flowers from going to seed and rhododendrons should be deadheaded too in order to give the plant energy for more flower production next year. Deadheading will also give your rhododendron a tidier appearance until next year's flowering period.
The Chelsea Chop which quite simply is a pruning technique that you can use on some of your herbaceous perennials to delay or extend the flowering period.
In every garden I visit, there are bags of Aldi UK's 99p compost lying in wait! Don't be afraid to use this thinking it might be too cheap to be true - it's perfect as a Spring mulch for all around your borders.
I had some bulbs lying around that I had forgotten to plant in the Autumn so I planted them in this planter on 22nd February and, a little later than would be seasonal, they are just glorious! Nothing ventured, nothing gained!
If you are trying to achieve that perfect circle of soil around the base of trees, use an old hula hoop. If it won't fit over the top over your tree, just snip it so you can flex it round the base. Easy when you know how!
I save all our eggshells through the Winter to scatter around the bases of those plants vulnerable to a slug attack like lupins, hostas and salvias.
It always looks better as it adds depth to the planting, if you group a few pots together, odd numbers work best.