Hurrah! The irrigation system is back online. Auto-Rain have disconnected zones 3&4 and the rest of the zones are working fine. In a week or two problem zones should be repaired too.
The garden has been without a working irrigation system during one of the warmest and driest Aprils I can remember. Peter and the team from Garden Associates and Lady Marshall have been watering the newly planted shrubs by hand but this was only ever going to be a stopgap measure so we are all very relieved that the system is running again.
The problem with zones 3 & 4 remain the accumulation of stones that prevent the valves from closing. If those can be replaced this problem should not reoccur.
Our irrigation system is over 20 years old which is quite venerable as these things go and the garden may require a new system in the next few years. Due to the preponderance of herbaceous plants any replacement system could only be installed outside the growing season, ideally in early winter. A full replacement would likely cost £8-10,000.
The existing system will be fine for this summer as long as the plants that obscure some of the sprinklers are trimmed back regularly. If the defective zones can be fixed the system will be good for a few more years yet.