Cal Wonder 300 TMR Sweet Bell Pepper Heirloom Seeds

Grow the classic bell-pepper shape and sweet crunch of Cal Wonder in the 300 TMR selection. These blocky, thick-walled peppers are usually four-lobed and approximately 3–4 inches across, making them a natural choice for stuffing, roasting, and fresh slicing. Pick them glossy green for crisp, mild flavor, or leave them on the plant to ripen red and develop greater sweetness.

Why Grow Cal Wonder 300 TMR?

• Thick-walled, blocky bells: Substantial flesh suits stuffed peppers, roasted halves, and crunchy raw strips.
• Green-to-red harvest: Enjoy usable green fruit or wait longer for fully red, sweeter peppers.
• Sweet, not hot: A no-heat bell pepper, listed at 0 Scoville Heat Units.
• TMR selection: TMR stands for Tobacco Mosaic Resistant. This selection is reported resistant to tobacco mosaic virus, but resistance does not mean immunity or protection from every disease.
• Open-pollinated heirloom: A non-GMO selection in the California Wonder family, suitable for seed saving with appropriate isolation and selection.

In the Kitchen

Fill green bells with rice, beans, or your favorite savory filling and bake until tender. Slice fresh peppers into salads and snack plates, dice them for fajitas and stir-fries, or roast ripe red peppers for their sweeter flavor. Freeze prepared strips or diced peppers for later cooked dishes.

Planting and Growing

Start indoors approximately 8–10 weeks before your expected outdoor planting date. Sow ¼ inch deep in seed-starting mix, provide steady warmth for germination, and give seedlings strong light after emergence. Keep moist without waterlogging. Harden plants off gradually and transplant after frost danger has passed, when soil and nights are reliably warm.

Choose full sun and fertile, well-drained soil, approximately pH 6.0–6.8. Space plants about 18 inches apart, allowing more room where needed for airflow and access. Plants are typically upright and about 18–24 inches tall under the supplier's growing conditions. Stake or cage if needed to support branches as fruit develops. Water consistently and avoid excessive nitrogen, which can favor foliage over fruit.

For square foot gardening, use 1 plant per sq ft (allow extra canopy room and support as needed). Where plants become crowded, give them more room rather than forcing the spacing. A roomy container with drainage can also work; monitor moisture carefully because pots dry faster than garden soil.

Harvest Details

Maturity: Approximately 75–90 days from transplant; green fruit is generally ready before fully red fruit, which takes additional time. Weather and plant establishment affect timing.
Fruit: Blocky, thick-walled bells, usually four-lobed and approximately 3–4 inches across.
Color: Green when immature, red when fully ripe.
Flavor: Mild and crisp green; sweeter when fully red.
Heat: Sweet bell pepper, 0 SHU.
Growth habit: Upright, branching plant; commonly about 18–24 inches tall.
Best uses: Stuffing, roasting, fresh slicing, salads, stir-fries, and freezing.
Botanical name: Capsicum annuum.
Type: Open-pollinated, non-GMO heirloom selection; frost-tender perennial commonly grown as a warm-season annual.
Seeds per packet: Approximately 25+ seeds.

Harvest when peppers reach useful size and feel firm. Snip the stem with clean scissors rather than pulling, which can damage branches. Leave selected fruit on the plant longer if you prefer fully red peppers.

Packed and shipped by Box Garden Seeds LLC — heirloom seeds grown without GMOs, selected for your garden.