How do you grow big cabbage?

QUESTION: How do you grow big cabbage? Is there particular variety I need to plant? -Kari R.

ANSWER: Growing big cabbage heads takes a bit of extra effort and time, but growing a giant cabbage takes some serious focus. If you are trying to break the record, your goal is to grow a cabbage head that is just over 138.25 pounds, as that is the size of the largest cabbage ever grown, which was cultivated by Scott Robb, a farmer from Alaska. Most gardeners, however, are just looking to get some bigger than average cabbage heads out of their garden. If you want to learn how to grow bigger cabbage heads, there are a few simple tricks that you can put into practice to help you along the way that will have you growing big cabbage heads in no time.

To grow big cabbages, you want to start out with seeds from other large cabbages, such as the tropic giant variety, which typically produces heads weighing up to 15 pounds and measuring one foot across. If you are trying your hand at growing that variety in a coastal area, start your seeds around January 10th, or if you’re growing the giant in an inland climate, wait until February 1st. The Tropic Giant is not the only large cabbage variety available, but it is among the largest.

If you are really looking to top that record, Bonnie Plants sell a variety called OS Cross, which produces cabbage heads that start at 30 to 50 pounds. However, assuming you want to grow varieties that are manageable in a small garden, you might want to scale it down a bit and select from one of the large dutch drumhead varieties such as Late Flat Dutch, Brunswick, or Perfection Drumhead Savoy, all of which typically produce cabbage heads weighing eight to ten pounds. Whatever variety you choose, here are some tips to help you get the biggest heads possible.

First, you will want to start your cabbage seeds indoors to give them extra time to grow larger before moving them outdoors. You will need a six to eight inch planting pot and some well-draining potting mix. Gently push the seeds one fourth of an inch into the soil and one inch apart and keep the soil moist. Place the pots in a location that receives lots of direct sun each day and a steady temperature between 60 and 70 degrees F.

Around the first of March in coastal regions and the first of April inland, your seedlings should be about ready to transplant into the garden. Before making the move, prepare the soil to get it ready to grow the biggest cabbages possible. To do this, you will need to add about eight cubic feet of compost for every 100 square feet of garden area that is devoted to cabbage growing. Mix the compost into the soil to a depth of six inches, raking the area smooth and irrigating to a depth of six inches as well.

Once you’ve prepared your beds it’s time to begin moving your cabbage seedlings. They need to be slowly acclimated to their new environment, so begin by leaving the pots in a lightly shaded area for one or two hours at first and increase the amount of time outside over the course of a week until they are ready to be permanently moved. When planting, make sure to give each seedling a plot that is large enough to grow the size heads that you want to cultivate.

Two weeks after planting, side dress your cabbages with a high-nitrogen 20-10-10 fertilizer, as big headed cabbages will need lots of nitrogen to grow extra large. Follow the directions on the fertilizer label for application, then water the fertilized area to a depth of three inches. Repeat the fertilization every two weeks. Provide at least one inch of water per week either from rain or manual watering. Keep the soil moist at all times to help prevent splitting but don’t allow the soil to become soggy or waterlogged.

Lastly, watch out for aphids, cabbage loopers, and webworms, all of which want to take a bite out of your cabbage before you can harvest it yourself. To rid yourself of aphids, spray the cabbage with an insecticidal soap spray covering the plant, then rinse with clear water. Look for cabbage loopers and pick them off manually, dropping them into a bucket of water. They are light green in color with white stripes. You will know they are around if you notice small holes in the cabbage’s leaves. Webworms are slightly smaller than loopers and also eat holes into the leaves, but they seem to prefer young cabbage over further developed heads. Webworms can also be picked off by hand and drowned in water.

That is everything you need to know to grow large cabbage heads. To summarize, select a variety that is known for producing large heads based on the size cabbages you want to cultivate. Start seeds indoors to allow your plants extra time to grow. Harden them off over the course of a week when moving outdoors. Space seedlings apart based on how large you want your cabbages to grow, allowing ample room for plants to develop large heads. Prepare the beds by working in lots of organic material and fertilize early and often, using a nitrogen-rich fertilizer every two to three weeks. Provide one inch of water per week, keeping the soil moist but never soggy at all times to avoid splitting. Watch out for bugs and caterpillars that want to eat your cabbages as much as you do and eliminate them using insecticidal soap and by picking them off by hand. Harvest your heads when they are full and firm when squeezed.