Guide de culture du Quince

Treat fire blight (Erwinia amylovora) as the defining risk: UC IPM rates pear and quince as extremely susceptible. Keep nitrogen light, since lush vegetative growth is what the bacterium exploits; do not irrigate during bloom; and cut blighted wood well below the visible margin (UC IPM advises removing all discoloured tissue plus a further 15 to 20 cm on trunk infections, UW-Madison at least 30 cm below symptoms), disinfecting shears between cuts.

Leave fruit on the tree to ripen fully and pick in October or November, once it has turned from light yellow to deep golden and is strongly aromatic, but before the first frosts. Cut the fruit off rather than pulling it, then let it mellow for six to eight weeks before cooking.

Flowers are self-fertile, so a single tree will crop, but yields are better with cross-pollination from a second quince. Bloom is in late spring, after the leaves emerge, which gives some natural escape from early spring frosts.

The root system is shallow and the tree is drought-susceptible, so water deeply through summer while the fruit is swelling, and shelter the site - quince is easily damaged by strong wind.

In wet summers watch for quince leaf blight (Diplocarpon mespili), which causes heavy leaf spotting and early defoliation and can cost the crop. Rake up and remove fallen leaves and avoid overhead irrigation; orchards already sprayed for scab tend to stay clean.

Do not plant near junipers. Cedar-quince rust (Gymnosporangium clavipes) needs two hosts to complete its cycle, one of them normally a juniper, so separating the two breaks the cycle.