How to Grow Waltham 29 Broccoli
Brassica oleracea var. italica 'Waltham 29'
Waltham 29 Broccoli is a reliable heirloom variety prized for its consistent head formation and excellent cold tolerance. Gardeners choose this brassica for its ability to thrive in cooler weather while resisting bolting, ensuring a steady harvest of tender heads throughout the season.
📷 Wikipedia: Brassica oleraceaStarting Waltham 29 Broccoli: indoors or direct sow?
🏠 Start indoors 4 weeks before your last spring frost, then move the seedlings outside.
Transplant seedlings outdoors once they have developed a few true leaves, ensuring the soil is cool and free of frost.
Soil, care & harvest
Prepare your soil by mixing in organic matter to reach a pH between 6.0 and 7.0. Sow seeds indoors four weeks before the last spring frost or direct sow outdoors two to six weeks prior. Press seeds gently into the soil at a depth of about one-quarter inch. Expect germination within seven to fourteen days, after which seedlings should be ready for transplanting.
Space plants eighteen to twenty-four inches apart in rows twelve inches apart to allow proper air circulation. While no trellising is needed, maintain consistent moisture by providing one to one-and-a-half inches of water weekly. Apply a light layer of mulch around the base to retain soil moisture and suppress weeds as the heads develop.
Watch for cabbage worms, aphids, flea beetles, and loopers; use row covers or insecticidal soap early. Prevent clubroot and leaf spots by rotating crops and avoiding overhead watering during humid periods. Harvest heads when firm but before they split, typically sixty-five to seventy-four days after sowing.
When to Plant Waltham 29 Broccoli
Planting windows vary by USDA hardiness zone. Look up yours by ZIP code.
| Zone | Start Indoors | Direct Sow | Harvest |
|---|---|---|---|
| Zone 1 | April – May | June – July | August – September |
| Zone 2 | April – May | May – July | July – September |
| Zone 3 | March – April | May – June | July – October |
| Zone 4 | March – April | April – June | July – October |
| Zone 5 | February – March | April – May | June – November |
| Zone 6 | February – March | April – May | June – November |
| Zone 7 | February – March | March – May | May – November |
| Zone 8 | January – February | March – April | May – December |
| Zone 9 | January | February – March | April – December |
| Zone 10 | January | January – March | March – December |
| Zone 11 | January | January – February | February – December |
| Zone 12 | January | January – February | February – December |
| Zone 13 | January | January – February | February – December |
Companion Plants for Waltham 29 Broccoli
✓ Good companions
Repels cabbage white butterflies and improves soil structure
Attracts beneficial insects and may improve broccoli flavor
Attracts beneficial wasps that parasitize cabbage worms
Grows well in broccoli's shade and doesn't compete for nutrients
Repels cabbage moths and other brassica pests with strong scent
Acts as trap crop for aphids and flea beetles, repels cabbage worms
Repels cabbage maggots and aphids with sulfur compounds
Shallow roots don't compete, benefits from broccoli's nitrogen fixation
✗ Keep away from
Attracts same pests like flea beetles and cabbage root fly
Compete for similar nutrients and may stunt broccoli growth
Allelopathic compounds inhibit brassica growth and development
Nutrition Facts
Per 100g serving (USDA FoodData Central)
