Keystone Giant Pepper produces softball-sized bell peppers on a sturdy, dependable plant that thrives across diverse climates. Developed from the California Wonder variety specifically to achieve even greater size, this heirloom cultivar has earned its place in gardens for decades as a reliable producer of massive, harvestable peppers in just 75 days. Growing to a compact 24 inches tall with a 18-inch spread, it fits nicely into most garden layouts while delivering the oversized yields home gardeners dream about.
18
Full Sun
Moderate
4-4
24in H x 18in W
—
Low
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Keystone Giant lives up to its name with truly massive, softball-sized bell peppers that dwarf standard varieties. The plant itself is remarkably stress-tolerant and widely adaptable, handling variable climates without flinching. What truly sets it apart for the home gardener is its documented resistance to mosaic virus, transforming what could be a frustrating season of disease pressure into a genuinely reliable harvest.
As a fresh bell pepper, Keystone Giant excels in any application where you want impressive size and visual presence. The enormous peppers are excellent for stuffing, as their substantial cavities and thick walls provide plenty of room for grain or vegetable fillings. They slice beautifully for fresh eating, raw garnishes, or cooking, and their sheer volume makes them economical for preserving, whether through freezing, roasting, or canning.
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Start seeds indoors 6 to 8 weeks before your last spring frost date. Sow seeds about 1/4 inch deep in warm, moist seed-starting mix and maintain soil temperatures around 70-80°F for reliable germination. Keep the soil consistently moist but not waterlogged, and provide bright light once seedlings emerge.
Transplant hardened-off seedlings outdoors after all danger of frost has passed and soil has warmed to at least 60°F. Space plants 18 inches apart in rows 36 inches apart. Handle seedlings carefully, as pepper transplants resent root disturbance; if using cell packs, gently loosen the root ball before planting. Plant at the same depth they were growing in their containers.
Keystone Giant peppers reach full maturity and harvest readiness in 75 days from transplanting. Harvest peppers when they have reached full size (softball-sized) and developed a glossy finish; you can harvest them at the mature green stage or wait for color development if desired. Cut peppers from the plant using a sharp knife rather than pulling, as this prevents damage to the brittle branches bearing heavy fruit. Leaving some peppers on the plant longer encourages continued flowering and additional fruit production.
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“Keystone Giant emerged from intentional breeding work to improve upon the already-respected California Wonder pepper. Plant breeders recognized that California Wonder had strong bones but wanted to push the size ceiling even higher, and Keystone Giant represents that successful effort. The variety has been a garden favorite for years, passing through generations of seed savers and home gardeners who valued its combination of massive fruit and dependable performance.”