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๐ŸProblem guide

Quince diseases and pests

The database lists 3 problems recorded on this crop. 3 of them can cost the whole harvest, and 3 survive in soil or debris into next season โ€” those are the ones that decide your rotation. The largest number are active in March.

Pressure through the year

The number of problems listed as active in each month. Pick a month to see what to sow, plant and harvest then.

Start from what you can see

What actually prevents them

  • Water at the base of the plant in the morning, never over the leaves. Splashing soil onto foliage is the delivery route for every problem listed here, and morning watering lets anything that does land dry before nightfall.

    Applies to: Brown Rot

  • Mulch the soil surface. A physical barrier between last season's spores and this season's lowest leaves removes the first infection of the year, which is the one that seeds all the others.

    Applies to: Brown Rot

  • Give the plants their full spacing 400ร—450 cm and keep the centre of each one open. Air moving through the planting dries the leaves faster, and leaf wetness duration is what turns a spore landing into an infection.

    Applies to: Apple Scab

  • Rotate this bed and everything else in the same family on at least a three-year cycle. 3 of the problems below survive in soil or crop debris between seasons, so returning the same crop to the same ground hands them the host they were waiting for.

    Applies to: Fire Blight, Apple Scab, Brown Rot

  • Clear and remove the spent crop at the end of the season rather than digging it in. Debris left on the surface is where the persistent problems overwinter, and next spring they start from your own bed rather than from somewhere else.

    Applies to: Fire Blight, Apple Scab, Brown Rot

  • Control sap-sucking insects early, before the population is obvious. Several of the problems here are carried plant to plant by aphids or thrips, and once a virus has arrived there is no treatment โ€” only the vector was ever treatable.

    Applies to: Fire Blight

  • Keep affected material out of the compost heap โ€” 2 of these survive a garden heap and come back with the finished compost. Bag it for municipal green waste, which is composted at temperatures a garden heap does not reach.

    Applies to: Fire Blight, Brown Rot

Every listed problem

Ordered by how much they can cost you.

Fungal diseases(2)

  • Olive-green to brown velvety blotches on leaves that later turn black; corky, cracked scabby lesions on fruit; early leaf drop in severe cases.

    How it spreads
    Wind-blown spores
    Compost
    Hot compost only
    Conditions
    6โ€“26ยฐC ยท humidity โ‰ฅ80% ยท wet leaves / rain
    First move
    Treat, then re-check in 5โ€“7 days

    Also at risk: Apple trees, Pear trees

  • Brown RotSevere

    Blossoms wilt and turn brown (blossom blight); fruit develops expanding brown firm rot covered with tan spore tufts; mummified fruit clings to the tree over winter.

    How it spreads
    Rain and irrigation splash
    Compost
    Keep out of the compost
    Conditions
    18โ€“28ยฐC ยท humidity โ‰ฅ85% ยท wet leaves / rain
    First move
    Treat, then re-check in 5โ€“7 days

    Also at risk: Plums, Cherries, Peaches

Bacterial diseases(1)

  • Fire BlightCritical

    Blossoms and shoots suddenly wilt, blacken and bend into a shepherd's crook as if scorched by fire; sunken cankers ooze amber bacterial droplets in warm weather.

    How it spreads
    Carried by insects
    Compost
    Keep out of the compost
    Conditions
    21โ€“30ยฐC ยท humidity โ‰ฅ70% ยท wet leaves / rain
    First move
    Remove affected material now

    Also at risk: Apple trees, Pear trees

Why rotation matters here

3 of these overwinter in the soil or in crop debris rather than on the plant. Pulling the sick plant does not remove them: they wait for the same host to come back to the same ground.

Problems of other crops