Yesterday afternoon when I logged onto Twitter, the first thing I saw was an open letter on the use of peat signed by some well-known professional horticulturists and illustrated with a picture of Peter Seabrook.  Earlier this year, I responded to some of the claims Peter Seabrook made about peat in Hort Week; today I’m responding to the claims made by the following professional horticulturists in an open letter, which was published by Garden Trade News.