The secret to the best-tasting broccoli is in the seasoning—not the spices, mind you, but the time of year. Broccoli that matures during cool weather produces healthy heads that are sweeter tasting than those you pick at any other time. Grow it this fall, and you will enjoy the most tender and flavorful broccoli you've ever eaten—long after the summer garden is a memory.
Broccoli grows best in fall because spring conditions may be unpredictable. Long, cool springs, for example, cause young transplants to form small, early heads; if temperatures heat up early in spring, heat-stressed broccoli opens its flower buds prematurely. And high temperatures as broccoli matures can cause bitter, loose heads to form, leaving you with smaller and less tasty florets. In fall, broccoli produces bigger and tastier heads, as plants mature during cooler weather.
When to Plant
You can easily figure the perfect time to plant broccoli seeds this fall. If you want to sow seeds directly in the garden, do so about 85 to 100 days before the average first fall frost in your area, which happens in mid to late summer in most places (read: any day now!). If you prefer to grow from transplants, figure the date for getting your plants in the ground by adding 10 days to the "days to maturity" for the variety you're growing, and then counting backwards from your expected first fall frost date. We've listed our favorite fall broccoli varieties, along with the number of days they need to mature, on the last page of this article.
Where to Plant
Broccoli grows best in full sun and where the soil is slightly acidic (pH between 6.0 and 6.8), fertile, and well-drained, yet consistently moist and rich in organic matter. The right pH and the organic matter help ensure that nutrients, particularly essential micronutrients like boron, are readily available. (A boron deficiency can cause broccoli to develop hollow stems, but adding too much is toxic to plants, so a soil test is essential.)
Fall broccoli has specific spacing requirements. If you're gardening intensively in a raised bed, space your plants 15 to 18 inches apart; for gardening in rows, set the transplants 18 to 24 inches apart within the row and space the rows 24 to 36 inches apart. Be sure to set transplants slightly deeper in the ground than they were in the pot.
Keep Them Nourished
Broccoli is a moderately heavy feeder, so work in 2 to 4 inches of rich compost or a thin layer of well-aged manure before planting. Rabbit manure is a personal favorite, though most any aged manure or compost produces big and tasty heads. After you've harvested a plant's central head, you can encourage extended side-shoot production by scratching a little nitrogen-rich fertilizer such as fish meal or aged manure into the soil around its base (this is known as sidedressing). The best time to sidedress sprouting types that have overwintered is in late winter or early spring when growth resumes.
Shelter from Cold
Freezing temperatures can cause chilling injury that turns buds purple and sometimes softens heads, though they are still good to eat. "I've had broccoli freeze solid, and when it thawed out it was fine," says Atina Diffley, co-owner of Gardens of Eagan Organic Farm, in Minnesota. Just don't let heads freeze and thaw repeatedly.
Offer cold-weather protection with floating row covers, which provide an additional 4 to 8°F worth of warmth, shielding harvests from heavy freezes and extending the season by up to four weeks. Or cover broccoli with tunnels or a coldframe, which can boost daytime temperatures by 10 to 30°F.
Protect Against Pests
Row covers provide some protection from pest insects, but the best protection is to grow healthy plants—and that begins with healthy soil, says Colby Eierman, director of gardens at COPIA: The American Center for Wine, Food & the Arts, in Napa, California. Insect pests are generally less prevalent in fall than in spring. But if your broccoli does suffer an infestation of destructive caterpillar pests such as cabbage loopers, you can control them with Bacillus thuringiensis var. kurstaki, a naturally occurring bacteria that stops the pests from chewing but is harmless to beneficial insects.
For best flavor, harvest broccoli heads while the buds are just starting to swell but before the yellow petals start to show. Keep an eye on the head, for when it begins to spread open, the individual buds start to flower. Harvest the central head by cutting the stalk at a slant, about 5 to 8 inches below the head. This encourages side-shoot production for continued harvests. Diffley says it's important to harvest broccoli in the morning before the plants heat up, because broccoli has a really high respiration rate. "Once the heat sets in, you need to cool it down quickly, or it's not going to hold up well and taste like it should," she says.
Now that you're set to grow the best-tasting broccoli ever, be sure to keep that flavor intact by not overcooking—broccoli is best when cooked until tender-crisp and still bright in color. In fact, Eierman says the chef at COPIA has a simple way of letting the flavor of broccoli shine: The florets are blanched and then shocked in an ice bath, then quickly stir-fried in olive oil. Of course, the best dishes begin with homegrown broccoli that's perfectly seasoned.
Broccoli is a cool-season vegetable with its roots in the Mediterranean region. Along with other cole crops, such as cauliflower, cabbage, and Brussels sprouts, broccoli is a descendant of wild cabbage. What's even wilder is that broccoli comes in two forms—okay, maybe three, depending on who you talk to.
The heading type forms one large head of flower buds on a central stalk, with some varieties forming harvestable side shoots once the central head is cut.
The sprouting type forms lots of small florets in the leaf axils.
The Romanesco type—that questionable third type—is unique, with spiraling, conical clusters ascending into apple green heads. It's neither broccoli nor cauliflower but rather in a class by itself.
The 'Arcadia' broccoli in our test garden is mulched with straw to control weeds yet allow water to reach the soil. Opposite: Broccoli tastes best and is most nutritious when harvested in the morning.
When broccoli begins to form heads, feed it with compost tea or other organic fertilizer to help maximize spear production.
Best Broccoli Varieties for Fall
In our test gardens around the United States and those of experts we interviewed, these varieties are the top broccoli performers for growing at the end of the season.
Variety Name 'Arcadia'
Days To Maturity 63
Description Vigorous plants with firm, frosty blue-green heads about 8 inches across, followed by plenty of side shoots.
Comments These disease-resistant plants are also tolerant of heat and cold stress.
Variety Name 'Flash'
Days to Maturity 50
Description Fast, early, and tasty harvests of deep green heads and outstanding fall flavor that's extra sweet. Medium 6-inch heads have tight beads and good side-shoot production once the central head is cut.
Comments Very heat-resistant and disease-tolerant.
Variety Name 'Gypsy'
Days to Maturity 58
Description Fast becoming a fall favorite among many market growers due to its great taste, uniform yield, and well-domed heads on large, healthy plants. Medium green heads with small- to medium-size beads are also great for fresh eating.
Comments Holds up to heat and tolerant of downy mildew.
Variety Name 'Marathon'
Days to Maturity 62 to 68
Description Large, beautiful blue-green heads with fine beads are deep and well domed, followed by good side-shoot production.
Comments Widely adapted and a good performer across the regions, with excellent cold tolerance.
Variety Name 'Premium Crop'
Days to Maturity 58 to 62
Description Vigorous grower and high yielder of delicately flavored, deep blue-green heads of fine quality. Large (9- to 10-inch) dome-shaped heads are compact with a fine bead; fall crops often produce side shoots.
Comments Disease- and heat-tolerant.
Variety Name 'Calabrese'
Days to Maturity 58 to 80
Description A prolific Italian heirloom producing tight, dark blue-green heads 3 to 6 inches across, followed by lots of tasty side shoots. Great fresh taste.
Comments Very disease-resistant and thrives in cool weather.
Variety Name 'DeCicco'
Days to Maturity 48 to 65
Description Italian heirloom producing earlier harvests than 'Calabrese', with smaller (3- to 4-inch) tender central heads on compact plants that mature over a long harvest period, followed by a bountiful supply of side shoots.
Comments Valued for its fine flavor and ease of growing.
Variety Name 'Early Purple Sprouting'
Days to Maturity 220 to 250
Description English heirloom sprouting type producing numerous smaller shoots rather than one main head. A good variety for overwintering in milder regions. Best planted in mid to late summer for harvests of small but sweet-tasting purple heads the following spring.
Comments Hardy to below 10°F.
Variety Name 'Rosalind'
Days to Maturity 60 to 65
Description Early-maturing, purple-headed broccoli producing 6- to 8-inch fine-textured heads in an eye-catching violet-purple that turn a brilliant emerald green when cooked. Better purple color than other purple types.
Comments Heat-tolerant; produces best-tasting heads during cooler fall weather.
Variety Name 'Umpqua'
Days to Maturity 55 to 60
Description Large central heads producing over a long harvest window followed by a generous offering of side shoots. Dark green heads are well domed and of excellent quality, with fine beads. Comments Has a sweet, tender flavor that some say is unsurpassed for an open-pollinated variety.
Burpee, Warminster, PA; 800-888-1447
Johnny's Selected Seeds, Winslow, ME; 877-564-6697
Pinetree Garden Seeds, New Gloucester, ME; 207-926-3400
Seeds Savers Exchange, Decorah, IA; 563-382-5990
Territorial Seed Company, Cottage Grove, OR; 800-626-0866