Pre-flower girdles on green varieties - act now

15 October 2015

Growers with green blocks at high risk of bud-rot infection should be considering a pre-flower girdle now to manage flower bud infection risk.

Sepal staining and leafspot are beginning to show on some Hayward and G14 blocks (pictured) particularly in colder locations or where higher levels of Psa infection have occurred this spring.

Pre-flower trunk girdling provides a tool for reducing Psa-V bud-rot and increasing fruit-set for both Hayward and Green14 varieties. Best results are achieved when applied around 30 days before flowering. Many orchards are now within, or fast approaching, this timing window.

For best results apply full girdles to both male and female vines and avoid girdling stressed plants. Choose a low-risk weather period, apply girdles to stumps in preference to young scions, girdle to the correct depth and ensure tools are sterilised between plants.

Even if sepal staining is already being seen, trial results suggest there is benefit in applying a pre-flower girdle.

This tool is strongly recommended for at-risk organic sites. Leave some vines un-girdled to gauge the effectiveness of this technique on your site.

Click here for further information on trunk girdling on the Zespri Canopy