Flexi-Spray allows hose output to be calibrated while giving easy access to out-of-the-way plants. It can also serve as a sprinkler and will retail at £29.99.
Hozelock UK managing director Bernard Shannon said: "Hozelock has a heritage of research and development, testing products in our own garden. We have also got Plant Heritage members to try these."
Plant Heritage quarantine officer Andrew Gaunt said: "You don't want to blast your seedlings and Flexi Spray gives you just what you want, from fine spray to pressure washer. It's a bit heavy, but robust and won't break."
Hozelock will also sell an irrigated plant tray called Growbag Waterer, which uses capillary matting to transfer water from a reservoir into the compost. It will retail at £24.99.
Also, its latest anti-kink Ultimate yellow hose comes with a 30-year guarantee.