Brussels sprout-specific resources:

Brussels Sprout Appreciation Society: Yup, it’s a thing. These folks love their sprouts!
https://www.facebook.com/Sproutaholics/

Brussels Sprout Club PHL: Yup, it’s a thing in Philadelphia, too. Find out more about what’s to love about Brussels sprouts.
Brussels Sprouts Club PHL

Ernie’s Pride: This company is all Brussels sprouts, all the time. Learn a little more about Brussels sprouts and pick up some new recipes.
https://brussels-sprouts.com/

General gardening resources:

Baker Creek Heirloom Seeds: This site bills itself as “America’s top source for pure heirloom seeds.” You can even order a print catalog for your own perusing.
https://www.rareseeds.com/

Bonnie Plants: Buy all your seedlings online, from this family-owned business that’s been around for 100+ years!
https://bonnieplants.com/

Burpee Seeds: One of the preeminent seed companies in the country, Burpee seeds and plants are available for all growing zones and for all seasons. Burpee guarantees each and every product. Order your seeds online!
https://www.burpee.com/

Dave’s Garden: Dave's Garden is one of the largest sites for gardeners in the world. It offers tens of thousands of encyclopedic files on plants, bugs, and birds, as well as helpful articles by gardening experts. The community also supports an open and safe place for advice, shared experiences, and an active seed and plant trade. There is even a user-reviewed vendor list of sites that sell plants and seeds.
https://davesgarden.com/

Farmtek: From seed-starting supplies to gardening tools and greenhouse kits, Farmtek caters to home gardeners and commercial farmers, large and small.
https://www.farmtek.com

Gardener’s Supply Company: Get innovative gardening products to help make your garden productive and your work more efficient and satisfying. From fertilizer and mulch to planters and pots, and from cages and trellises to snippers and canning jar sets, find what you need for your garden.
https://www.gardeners.com/buy/gardening/tomato-growing/

Growspan Greenhouse Structures: Find a greenhouse for any gardening style—from hobby gardening to commercial applications. All greenhouses are made in the U.S.
https://www.growspan.com/

National Gardening Association: With over 1 million members, the National Gardening Association is dedicated to promoting gardening and providing members with tools and resources for improving their skills.
https://garden.org/

Nutrition Value: An online database to help you quickly discover the nutritional value of almost any food, including individual items and prepared dishes—both cooked and raw.
https://www.nutritionvalue.org/

Plant Natural: A great resource for managing an organic garden, Plant Natural provides advice, guidance, and products—carrying everything from organic fertilizers and natural pest control products (including beneficial insects) to compost bins and natural cleaning products for your home.
https://www.planetnatural.com/

Seed Savers Exchange: An organization “dedicated to the preservation of heirloom seeds.” As a nonprofit, Seed Savers Exchange aims to conserve and promote America’s culturally diverse, but endangered garden and food crop heritage for future generations by collecting, growing, and sharing heirloom seeds and plants.
https://www.seedsavers.org/

Stark Bro’s: You can buy food seedlings and even fruit trees online from this 200-year-old business.
https://www.starkbros.com

True-Leaf Market: This organization has been a source for non-GMO seeds since 1974. You can get seeds for almost any crop plant here.
https://www.trueleafmarket.com

U.S. Composting Council: This group sets the standards for composting, including manufacturing and utilization that are central to creating healthy soils, clean air and water, a stable climate, and a sustainable society.
https://www.compostingcouncil.org/

USDA Plant Hardiness Zone Map: Check out which zone your home garden is located in when you review this map.
https://planthardiness.ars.usda.gov/

Do you have Brussels sprout resources that you find essential to growing your Brussels sprout garden? Please tell us which additional resources you find valuable.