Caring for Brussels sprouts is much like other vegetables in the cole crop family. They like 6-8 hours a day of full sun, daytime temperatures of 70 degrees or lower, well-draining soil with a neutral pH and 1-1.5 inches of water a week to keep the soil moist. Consistent watering produces the best sprout development. In hot climates, partial shading is a must.

The biggest threats to Brussels sprout plants are aphids, cabbage worms, cabbage looper and root maggots. Fabric row covers and hoop tunnels will protect against pests. A clean garden and good air circulation lower the risk of fungal diseases.

For indoor Brussels sprout seeding, begin 4-6 weeks before the final spring frost. Fill cell trays or pots with sterile seed starter mix and plant three seeds per tray 1/4-1/2-inch deep. Water regularly to keep the soil moist; when seedlings appear, move them to a sunny area or add grow lights. Apply a half-strength seed fertilizer once a week after the first true leaf appears and increase it to twice a week with the second true leaf.

If you are seeding outdoors, sow three seeds every 18 inches. Once most of the seedlings have a few true leaves, thin them to one per spot.

Brussels sprouts can be planted in the spring after the final frost or the mid-to-late summer for a fall harvest. Raised garden beds work well because they have good drainage and maintain a more consistent temperature. "Harden off" seedlings for a week before transplanting by increasingly exposing them to outdoor conditions. Place the seedlings 18-24 inches apart in rows, water them thoroughly and add mulch for moisture retention. You can plant Brussels sprouts in containers, too; use one 5-7 gallon pot per seedling with lots of drainage holes.

These heavy-feeding veggies need regular fertilization to grow their best. Work organic compost or a balanced fertilizer into the soil at the initial planting. Once the plants are six inches tall, start applying a high nitrogen fertilizer every 3-4 weeks. You should not fertilize while buds are forming because this can make the sprouts soft. Do regular soil testing or watch for signs such as stunted growth (general nutrient deficiency) or yellow leaves (low nitrogen).

Unlike many other vegetables, Brussels sprouts like some cold. A light frost even helps them taste sweeter. That said, temperatures below 10 degrees can cause harm. To overwinter in the garden, add a thick mulch layer and consider frost cloths or floating row covers. You can also carefully remove the plant from the ground, cover the roots in damp sand and store them in a dry area.

Regular and strategic pruning once the sprouts start developing will give you a healthy, bountiful and more uniform harvest. Once a week, remove the lowest few leaves and any damaged leaves. When the plant is about two feet tall or about 3-4 weeks before harvest, pinch the top 1-2 inches off to stimulate sprout growth.
This vegetable is ready for harvesting when the sprouts are 1-2 inches large, firm, tightly packed and haven’t split open. Cut the entire stalk off at the base or pick individual sprouts. By storing the sprouts in a refrigerator drawer or cool garage, they can last up to two weeks.