Deadheading

Hi Minorbob - "Deadheading" is really removing the seed-making bits of the plant (ie. the 'dead' flowers) so it makes more flowers, trying to make more seed. (It's all about reproduction, in the end!) Apparently, the loss of the seedhead sends an hormonal signal to the plant and it responds by triggering more flowering. To keep the plant looking tidy, I chop off the old flowers as far down their stalks as I can reasonably manage - otherwise, you end up with a lot of withered stalks waving around. But be careful, some (many?) plants put out new growth from the base of the flower stalk so leave a few millimetres of the stalk so you don't accidentally damage any growing points. Hope this helps . . .

Here is a link to RHS on deadheading

http://www.rhs.org.uk/advice/profiles0700/deadheading.asp

should cover whatever you haave in mind

Some plants also produce a new bud from just below the dead one - so it pays to learn which plants do this, or you'll lose flowers! Here are a few examples - Centaurea montana, Salvia, Veronica, Hebe, Buddleja. I am sure that there are more - they were just some of the plants in my garden.

You usually just have a look at teh flower stem and cut it back as far as there is a new bud already developing or a leaf node (where a leave is growing from the stem) where a new flower bud is likely to develop. I don't bother deadheading plants that produce thousands of tiny flowers - just the ones with big flowers like roses, dahlias, sweetpeas and cosmos.