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Black Krim · February 29, 2020

In an effort to manage scab, i keep looking for info.

"How to Prevent & Control Common Potato Scab
Unlike most of the other vegetables who prefer a pH approaching neutral (7.00) potatoes are best grown in soil with a pH of 5.5 which discourages the Streptomyces Scabies bacteria and therefore the scab. Fertilising with sulphate of ammonia or superphosphate will acidify soils and should be considered for limey soils with a naturally high pH. Do not lime soil prior to planting potatoes unless the soil pH is very low, below 5.00.

Avoid excess use of nitrogen rich fertiliser such as sulphate of ammonia as over-application of nitrogen delays the onset of tuber bulking which prolongs the period that the plant is susceptible to scab.

Increasing the level of organic matter in the soil and thereby retaining moisture in the soil combined with regular watering, ideally each day for the first six weeks after planting will also reduce the severity of symptoms. Keeping the seed tuber skin wet stops the disease taking hold

Crop rotation will also assist in control of potato scab. Growing potatoes in the same place over consecutive years will build up the level of bacteria in the soil. Be aware that radishes, beets, turnips carrots and red clover are all capable of carrying common scab.

There are no chemical controls available to home growers.

Common Potato Scab Resistant Varieties
If common potato scab is persistent problem on your plot then consider growing resistant varieties of potato in addition to the control methods above. Resistant potato varieties include:

Accent
Anna
Anya
Arran Pilot
Avondale
Balmoral
Banba
Camelot
Cara
Carlingford
Carnaval
Challenger
Chaski
Chopin
Claret
Cosmos
Courlan
Druid
Electra
Ellie
Galactica
Golden Wonder
Habibi
Inca Bella
Inca Dawn
Jester
King Edward
La Strada
Lady Christl
Lanorma
Lulu
Malin
Manhattan
Mayan Gold
Mayan Queen
Mayan Twilight
Melody
Mimi
Morene
Nadine
Orchestra
Paru
Pentland Crown
Picasso
Piccolo Star
Pink Gypsy
Pizazz
Russet Burbank
Saturna
Savanna
Avoid planting varieties very susceptible to common scab
like:
Ambassador
Blue Danube
Duke Of York
Emma
Foremost
Horizon
Lady Claire
Maris Piper
Maxine
Mayan Star
Mistay
Mustang
Panther
Red Duke Of York
Rudolph
Setanta
Shelford
Smith’s Comet
Spunta
Tresdale
Ulster Chieftain
Up-to-date
Zohar
"

February 29, 2020	#14
Black Krim Tomatovillian™ Join Date: Dec 2016 Location: New England Posts: 661	In an effort to manage scab, i keep looking for info. "How to Prevent & Control Common Potato Scab Unlike most of the other vegetables who prefer a pH approaching neutral (7.00) potatoes are best grown in soil with a pH of 5.5 which discourages the Streptomyces Scabies bacteria and therefore the scab. Fertilising with sulphate of ammonia or superphosphate will acidify soils and should be considered for limey soils with a naturally high pH. Do not lime soil prior to planting potatoes unless the soil pH is very low, below 5.00. Avoid excess use of nitrogen rich fertiliser such as sulphate of ammonia as over-application of nitrogen delays the onset of tuber bulking which prolongs the period that the plant is susceptible to scab. Increasing the level of organic matter in the soil and thereby retaining moisture in the soil combined with regular watering, ideally each day for the first six weeks after planting will also reduce the severity of symptoms. Keeping the seed tuber skin wet stops the disease taking hold Crop rotation will also assist in control of potato scab. Growing potatoes in the same place over consecutive years will build up the level of bacteria in the soil. Be aware that radishes, beets, turnips carrots and red clover are all capable of carrying common scab. There are no chemical controls available to home growers. Common Potato Scab Resistant Varieties If common potato scab is persistent problem on your plot then consider growing resistant varieties of potato in addition to the control methods above. Resistant potato varieties include: Accent Anna Anya Arran Pilot Avondale Balmoral Banba Camelot Cara Carlingford Carnaval Challenger Chaski Chopin Claret Cosmos Courlan Druid Electra Ellie Galactica Golden Wonder Habibi Inca Bella Inca Dawn Jester King Edward La Strada Lady Christl Lanorma Lulu Malin Manhattan Mayan Gold Mayan Queen Mayan Twilight Melody Mimi Morene Nadine Orchestra Paru Pentland Crown Picasso Piccolo Star Pink Gypsy Pizazz Russet Burbank Saturna Savanna Avoid planting varieties very susceptible to common scab like: Ambassador Blue Danube Duke Of York Emma Foremost Horizon Lady Claire Maris Piper Maxine Mayan Star Mistay Mustang Panther Red Duke Of York Rudolph Setanta Shelford Smith’s Comet Spunta Tresdale Ulster Chieftain Up-to-date Zohar "