Heat Treated Onion Sets
Make growing your own onions a breeze with Mr Fothergill's heat-treated onion sets. The best choice for beginners, or an easy shortcut for experienced gardeners, heat-treated onion sets grow and establish much more rapidly. This means larger bulbs and higher yields, with virtually no risk of premature ‘bolting’.
Expertly heat-treated for several months, these onion sets will arrive at your door ready for immediate planting. Choose from many popular varieties, including the AGM-winning Red Baron, known for its beautiful crimson-skinned bulbs. Beginners will appreciate our reliable Stuttgarter Riesen sets, which boast great disease resistance. Discover our full range of heat-treated onion sets below.
{"id":466134303031,"handle":"heat-treated-onions","title":"Heat Treated Onion Sets","updated_at":"2025-01-23T15:41:10+00:00","body_html":"\u003cp\u003eMake growing your own onions a breeze with Mr Fothergill's heat-treated onion sets. The best choice for beginners, or an easy shortcut for experienced gardeners, heat-treated onion sets grow and establish much more rapidly. This means larger bulbs and higher yields, with virtually no risk of premature ‘bolting’.\u003c\/p\u003e\n\u003cp\u003eExpertly heat-treated for several months, these \u003ca href=\"\/collections\/onion-sets\"\u003eonion sets\u003c\/a\u003e will arrive at your door ready for immediate planting. Choose from many popular varieties, including the AGM-winning Red Baron, known for its beautiful crimson-skinned bulbs. Beginners will appreciate our reliable Stuttgarter Riesen sets, which boast great disease resistance. Discover our full range of heat-treated onion sets below.\u003c\/p\u003e","published_at":"2023-10-31T09:39:06+00:00","sort_order":"best-selling","template_suffix":"","disjunctive":false,"rules":[{"column":"tag","relation":"equals","condition":"Collection:Heat Treated Onion Sets"}],"published_scope":"global"}
[{"id":8334945583415,"title":"Onion (Heat Treated) Red Baron AGM Sets","handle":"onion-heat-treated-red-baron-agm-sets","description":"\u003cp\u003eOnion Red Baron AGM is the best red-skinned variety, the attractive, crimson-skinned bulbs when sliced reveal contrasting red and white rings, making it most attractive on the plate. Red Baron has a lovely, robust flavour and is a remarkably good keeper. The perfect partner for Cupido.\u003cbr\u003e\u003cbr\u003eHeat treating our onion sets is rather like turbo-charging them! This totally natural process takes several months, but the process means they establish and grow very rapidly, giving higher yields - and with virtually no risk of prematurely running to seed or 'bolting'.\u003cbr\u003e\u003cb\u003e\u003cbr\u003eAll of our bulbs are certified as disease and virus free.\u003cbr\u003e\u003cbr\u003eDelivered in 250g packs, each pack containing approx. 70 sets.\u003c\/b\u003e\u003c\/p\u003e","published_at":"2023-05-17T17:27:30+01:00","created_at":"2023-05-17T17:27:30+01:00","vendor":"Mr Fothergill's","type":"ONIONS\/GARLIC\/SHALLOTS","tags":["badge:RHS award","badges:exhibition variety","Collection:all products (excluding drop ship HARDWARE)","Collection:Heat Treated Onion Sets","Collection:MRF all products exc all hardware","Collection:Onion Sets","Collection:Onions Shallots And Garlic","Collection:Spring Planting Onions","harvest:august","harvest:september","osg:no colls","product family:onion","product type:bulbs","shallots and garlic","sow outdoors:april","sow outdoors:march"],"price":585,"price_min":585,"price_max":585,"available":true,"price_varies":false,"compare_at_price":585,"compare_at_price_min":585,"compare_at_price_max":585,"compare_at_price_varies":false,"variants":[{"id":45384714125623,"title":"Default Title","option1":"Default Title","option2":null,"option3":null,"sku":"41706","requires_shipping":true,"taxable":false,"featured_image":null,"available":true,"name":"Onion (Heat Treated) Red Baron AGM Sets","public_title":null,"options":["Default Title"],"price":585,"weight":250,"compare_at_price":585,"inventory_management":"shopify","barcode":null,"requires_selling_plan":false,"selling_plan_allocations":[],"quantity_rule":{"min":1,"max":null,"increment":1}}],"images":["\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-010z.jpg?v=1729938812"],"featured_image":"\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-010z.jpg?v=1729938812","options":["Title"],"media":[{"alt":"Onion (Heat Treated) Red Baron AGM Sets","id":39855832858935,"position":1,"preview_image":{"aspect_ratio":1.0,"height":600,"width":600,"src":"\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-010z.jpg?v=1729938812"},"aspect_ratio":1.0,"height":600,"media_type":"image","src":"\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-010z.jpg?v=1729938812","width":600}],"requires_selling_plan":false,"selling_plan_groups":[],"content":"\u003cp\u003eOnion Red Baron AGM is the best red-skinned variety, the attractive, crimson-skinned bulbs when sliced reveal contrasting red and white rings, making it most attractive on the plate. Red Baron has a lovely, robust flavour and is a remarkably good keeper. The perfect partner for Cupido.\u003cbr\u003e\u003cbr\u003eHeat treating our onion sets is rather like turbo-charging them! This totally natural process takes several months, but the process means they establish and grow very rapidly, giving higher yields - and with virtually no risk of prematurely running to seed or 'bolting'.\u003cbr\u003e\u003cb\u003e\u003cbr\u003eAll of our bulbs are certified as disease and virus free.\u003cbr\u003e\u003cbr\u003eDelivered in 250g packs, each pack containing approx. 70 sets.\u003c\/b\u003e\u003c\/p\u003e"},{"id":8334942535991,"title":"Heat Treated Onion Set Collection","handle":"heat-treated-onion-set-collection","description":"\u003cp\u003eThe collection consists of two of the best heat treated onion varieties.\u003cbr\u003e\u003cbr\u003e\u003cb\u003eCupido\u003c\/b\u003e A recent introduction that is becoming increasingly popular amongst commercial growers. Giving a high yield, it produces consistently round onions with an attractive golden yellow colour. With a perfect slightly sharp taste and crispness this variety will keep you going right through the winter as stores well.\u003cbr\u003e\u003cbr\u003e\u003cb\u003eRed Baron AGM\u003c\/b\u003e The best red-skinned variety, the attractive, crimson-skinned bulbs when sliced reveal contrasting red and white rings, making it most attractive on the plate. Red Baron has a lovely, robust flavour and is a remarkably good keeper. The perfect partner for Cupido.\u003cbr\u003e\u003cbr\u003eHeat treating our onion sets is rather like turbo-charging them! This totally natural process takes several months, but the process means they establish and grow very rapidly, giving higher yields - and with virtually no risk of prematurely running to seed or 'bolting'.\u003cbr\u003e\u003cbr\u003e\u003cb\u003eAll of our bulbs are certified as disease and virus free.\u003cbr\u003e\u003cbr\u003eDelivered in 250g packs, each pack containing approx. 70 sets.\u003c\/b\u003e\u003c\/p\u003e","published_at":"2023-05-17T17:26:06+01:00","created_at":"2023-05-17T17:26:06+01:00","vendor":"Mr Fothergill's","type":"ONIONS\/GARLIC\/SHALLOTS","tags":["Collection:all products (excluding drop ship HARDWARE)","Collection:Heat Treated Onion Sets","Collection:MRF all products exc all hardware","Collection:Onion Sets","Collection:Onions Shallots And Garlic","Collection:Spring Planting Onions","harvest:august","harvest:september","product family:onion","product type:bulbs","product type:collection","shallots and garlic","sow outdoors:april","sow outdoors:march"],"price":970,"price_min":970,"price_max":970,"available":true,"price_varies":false,"compare_at_price":970,"compare_at_price_min":970,"compare_at_price_max":970,"compare_at_price_varies":false,"variants":[{"id":45384699117879,"title":"Default Title","option1":"Default Title","option2":null,"option3":null,"sku":"41056","requires_shipping":true,"taxable":false,"featured_image":null,"available":true,"name":"Heat Treated Onion Set Collection","public_title":null,"options":["Default Title"],"price":970,"weight":500,"compare_at_price":970,"inventory_management":"shopify","barcode":null,"requires_selling_plan":false,"selling_plan_allocations":[],"quantity_rule":{"min":1,"max":null,"increment":1}}],"images":["\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-081z.jpg?v=1729937809"],"featured_image":"\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-081z.jpg?v=1729937809","options":["Title"],"media":[{"alt":"Heat Treated Onion Set Collection","id":39855836201271,"position":1,"preview_image":{"aspect_ratio":1.0,"height":800,"width":800,"src":"\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-081z.jpg?v=1729937809"},"aspect_ratio":1.0,"height":800,"media_type":"image","src":"\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-081z.jpg?v=1729937809","width":800}],"requires_selling_plan":false,"selling_plan_groups":[],"content":"\u003cp\u003eThe collection consists of two of the best heat treated onion varieties.\u003cbr\u003e\u003cbr\u003e\u003cb\u003eCupido\u003c\/b\u003e A recent introduction that is becoming increasingly popular amongst commercial growers. Giving a high yield, it produces consistently round onions with an attractive golden yellow colour. With a perfect slightly sharp taste and crispness this variety will keep you going right through the winter as stores well.\u003cbr\u003e\u003cbr\u003e\u003cb\u003eRed Baron AGM\u003c\/b\u003e The best red-skinned variety, the attractive, crimson-skinned bulbs when sliced reveal contrasting red and white rings, making it most attractive on the plate. Red Baron has a lovely, robust flavour and is a remarkably good keeper. The perfect partner for Cupido.\u003cbr\u003e\u003cbr\u003eHeat treating our onion sets is rather like turbo-charging them! This totally natural process takes several months, but the process means they establish and grow very rapidly, giving higher yields - and with virtually no risk of prematurely running to seed or 'bolting'.\u003cbr\u003e\u003cbr\u003e\u003cb\u003eAll of our bulbs are certified as disease and virus free.\u003cbr\u003e\u003cbr\u003eDelivered in 250g packs, each pack containing approx. 70 sets.\u003c\/b\u003e\u003c\/p\u003e"},{"id":8335145271607,"title":"Onion (Heat Treated) Cupido Sets","handle":"onion-heat-treated-cupido-sets","description":"\u003cp\u003eA recent introduction that is becoming increasingly popular amongst commercial growers. Giving a high yield, it produces consistently round onions with an attractive golden yellow colour. With a perfect slightly sharp taste and crispness this variety will keep you going right through the winter as stores well.\u003cbr\u003e\u003cbr\u003eHeat treating our onion sets is rather like turbo-charging them! This totally natural process takes several months, but the process means they establish and grow very rapidly, giving higher yields - and with virtually no risk of prematurely running to seed or 'bolting'.\u003cbr\u003e\u003cbr\u003e\u003cb\u003eAll of our bulbs are certified as disease and virus free.\u003cbr\u003e\u003cbr\u003eDelivered in 250g packs, each pack containing approx. 70 sets.\u003c\/b\u003e\u003c\/p\u003e","published_at":"2023-05-17T19:21:08+01:00","created_at":"2023-05-17T19:21:08+01:00","vendor":"Mr Fothergill's","type":"ONIONS\/GARLIC\/SHALLOTS","tags":["Collection:all products (excluding drop ship HARDWARE)","Collection:Heat Treated Onion Sets","Collection:MRF all products exc all hardware","Collection:Onion Sets","Collection:Onions Shallots And Garlic","Collection:Spring Planting Onions","harvest:august","harvest:october","harvest:september","osg:no colls","product family:onion","product type:bulbs","shallots and garlic","sow outdoors:april","sow outdoors:march"],"price":585,"price_min":585,"price_max":585,"available":true,"price_varies":false,"compare_at_price":585,"compare_at_price_min":585,"compare_at_price_max":585,"compare_at_price_varies":false,"variants":[{"id":45385611477303,"title":"Default Title","option1":"Default Title","option2":null,"option3":null,"sku":"54058","requires_shipping":true,"taxable":false,"featured_image":null,"available":true,"name":"Onion (Heat Treated) Cupido Sets","public_title":null,"options":["Default Title"],"price":585,"weight":250,"compare_at_price":585,"inventory_management":"shopify","barcode":null,"requires_selling_plan":false,"selling_plan_allocations":[],"quantity_rule":{"min":1,"max":null,"increment":1}}],"images":["\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-080z.jpg?v=1729938812"],"featured_image":"\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-080z.jpg?v=1729938812","options":["Title"],"media":[{"alt":"Onion (Heat Treated) Cupido Sets","id":39855228911927,"position":1,"preview_image":{"aspect_ratio":1.0,"height":800,"width":800,"src":"\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-080z.jpg?v=1729938812"},"aspect_ratio":1.0,"height":800,"media_type":"image","src":"\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-080z.jpg?v=1729938812","width":800}],"requires_selling_plan":false,"selling_plan_groups":[],"content":"\u003cp\u003eA recent introduction that is becoming increasingly popular amongst commercial growers. Giving a high yield, it produces consistently round onions with an attractive golden yellow colour. With a perfect slightly sharp taste and crispness this variety will keep you going right through the winter as stores well.\u003cbr\u003e\u003cbr\u003eHeat treating our onion sets is rather like turbo-charging them! This totally natural process takes several months, but the process means they establish and grow very rapidly, giving higher yields - and with virtually no risk of prematurely running to seed or 'bolting'.\u003cbr\u003e\u003cbr\u003e\u003cb\u003eAll of our bulbs are certified as disease and virus free.\u003cbr\u003e\u003cbr\u003eDelivered in 250g packs, each pack containing approx. 70 sets.\u003c\/b\u003e\u003c\/p\u003e"},{"id":8335145533751,"title":"Onion (Heat Treated) Rosanna Sets","handle":"onion-heat-treated-rosanna-sets","description":"\u003cp\u003eWe have been so impressed with Rosanna at recent trials that we think we have gone one better than the Sweet Rosy we introduced last year! Rosanna is a hybrid onion bred in the UK for our climate and has been crossed with the Rose de Roscoff Onion that was well known as the onion sold in the UK by the traditional French onion sellers. The pink blush continues once peeled with the stunning pink hues running right through the layers. With a unique sweet and fruity taste these are perfect for eating raw in salads as well as many cooked dishes - a gourmet onion due to its melt in the mouth flavour!\u003cbr\u003e\u003cbr\u003eHeat treating our onion sets is rather like turbo-charging them! This totally natural process takes several months, but the process means they establish and grow very rapidly, giving higher yields - and with virtually no risk of prematurely running to seed or 'bolting'.\u003cbr\u003e\u003cbr\u003e\u003cb\u003eAll of our bulbs are certified as disease and virus free.\u003cbr\u003e\u003cbr\u003eDelivered in 250g packs, each pack containing approx. 70 sets.\u003c\/b\u003e\u003c\/p\u003e","published_at":"2023-05-17T19:21:22+01:00","created_at":"2023-05-17T19:21:22+01:00","vendor":"Mr Fothergill's","type":"ONIONS\/GARLIC\/SHALLOTS","tags":["Collection:all products (excluding drop ship HARDWARE)","Collection:Heat Treated Onion Sets","Collection:MRF all products exc all hardware","Collection:Onion Sets","Collection:Onions Shallots And Garlic","Collection:Spring Planting Onions","harvest:august","harvest:october","harvest:september","osg:no colls","product family:onion","product type:bulbs","shallots and garlic","sow outdoors:april","sow outdoors:march"],"price":635,"price_min":635,"price_max":635,"available":true,"price_varies":false,"compare_at_price":635,"compare_at_price_min":635,"compare_at_price_max":635,"compare_at_price_varies":false,"variants":[{"id":45385612296503,"title":"Default Title","option1":"Default Title","option2":null,"option3":null,"sku":"54044","requires_shipping":true,"taxable":false,"featured_image":null,"available":true,"name":"Onion (Heat Treated) Rosanna Sets","public_title":null,"options":["Default Title"],"price":635,"weight":250,"compare_at_price":635,"inventory_management":"shopify","barcode":null,"requires_selling_plan":false,"selling_plan_allocations":[],"quantity_rule":{"min":1,"max":null,"increment":1}}],"images":["\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-077z.jpg?v=1729938811"],"featured_image":"\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-077z.jpg?v=1729938811","options":["Title"],"media":[{"alt":"Onion (Heat Treated) Rosanna Sets","id":39855227994423,"position":1,"preview_image":{"aspect_ratio":1.0,"height":800,"width":800,"src":"\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-077z.jpg?v=1729938811"},"aspect_ratio":1.0,"height":800,"media_type":"image","src":"\/\/mr-fothergills.co.uk\/cdn\/shop\/files\/ONI-077z.jpg?v=1729938811","width":800}],"requires_selling_plan":false,"selling_plan_groups":[],"content":"\u003cp\u003eWe have been so impressed with Rosanna at recent trials that we think we have gone one better than the Sweet Rosy we introduced last year! Rosanna is a hybrid onion bred in the UK for our climate and has been crossed with the Rose de Roscoff Onion that was well known as the onion sold in the UK by the traditional French onion sellers. The pink blush continues once peeled with the stunning pink hues running right through the layers. With a unique sweet and fruity taste these are perfect for eating raw in salads as well as many cooked dishes - a gourmet onion due to its melt in the mouth flavour!\u003cbr\u003e\u003cbr\u003eHeat treating our onion sets is rather like turbo-charging them! 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These onion sets are slow to bolt and offer improved disease resistance, making them perfect for beginner gardeners.\u003c\/p\u003e\u003cp\u003e\u003cbr\u003e\u003c\/p\u003e\u003cp\u003eWith a medium-hot flavour, they are ideal for a variety of dishes. 'Stuttgarter Riesen' is especially high-yielding, ensuring an abundant harvest for storage or immediate use in your cooking.\u003c\/p\u003e"}]
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Why Choose Our Heat Treated Onion Sets?
Onions are incredibly versatile: a staple in everything from soups and sandwiches to pasta sauces. Growing your own lets you enjoy the freshest bulbs possible, with an unbeatable crisp texture and home-grown flavour.
Heat-treated onion sets are quicker and easier to grow than onion seeds, making them great for busy gardeners. The bulbs are carefully heated and cooled over several months – a natural process which kills the sprout stalk. This leads to faster growth and bigger onions and also prevents premature running to seed (‘bolting’).
Our heat-treated onions can be planted directly in the ground or grown in pots. Pair them with bushy tomato plants or dwarf beans for a productive container vegetable garden.
Order Our Heat Treated Onion Sets Today
Here at Mr Fothergill's, we believe that growing your own vegetables should be simple, fun, and rewarding for everyone. All of our onion, garlic, and shallot sets are expertly grown, carefully hand selected and delivered to your door at the perfect time for planting.
Order your heat-treated onion sets today and start growing the kitchen garden of your dreams – 100% satisfaction guaranteed.