Broccoli is a healthy vegetable that can be easily cultivated in your container garden. It is high in Vitamins A and D and can be eaten either raw as an appetizer or cooked as a main dish either steamed or stir-fried.
It is a hardy vegetable that can easily be grown by those who are just starting with container gardening. When growing broccoli in containers, careful attention can give you a yield that can go beyond the harvesting period. If weather conditions are perfect, your broccoli can give you a great harvest in spring and fall.
There are several recommended varieties of broccoli available for you to choose from. Premium Crop, Green Valiant, Top Star, and Prominence all grow within 60 days. Royal Purple head needs 90 days for mature growth while Green Comet and Packman need 40 and 56 days respectively to reach maturity.
Starting your cultivation
Be sure to choose an area that has full sun but with light shade when growing broccoli in pots. Pots can trap heat, increasing soil temperature. This is not beneficial to broccoli for it is a cool-weather plant. Too warm environment or weather will cause your broccoli buds to bolt early, producing a woody and tasteless harvest.
It is best to follow the right season for planting broccoli to prevent this from happening.
The specifications of your pot or container
Broccoli can grow up to 3 feet wide and as much as 15 inches high. Choose a container that is at least 8 inches deep and 20 inches wide for a single crop. If you wish to grow multiple plants, a larger container is necessary for they must have adequate space for growth.
If you live in cool weather areas, you can use terra cotta pots. If you have a warmer climate, plastic or wood containers can be used as they do not absorb heat like terra cotta pots.
You may opt to choose a pot that is light-colored so it would reflect heat rather than absorb it. It is easier to warm up a crop when growing broccoli in containers than it is to reduce the temperature.
Drill holes at the bottom and at two opposite ends to help facilitate drainage.
Line the bottom of your container with small pieces of terra cotta pots, small pebbles, or a fiberglass mesh to help prevent soil erosion.
Preparing your soil or potting mix
Do not use your garden soil as your growing medium. Garden soil can harm your broccoli as it has numerous pathogens such as fungus, bacteria, and viruses.
Buy a potting mix in your local garden store for this purpose. The potting mix is a mixture of perlite, vermiculite, and peat moss that absorbs water but drains well. It is advised that you invest in a high-quality potting mix as cheap ones eventually hold in too much water and clump together, causing your broccoli roots to rot.
Adjust the pH of your potting soil to 6.0-6.8 with the use of either lime to increase the pH or sulfur to decrease it. Incorporate a good amount of compost into your potting mix to nourish the soil when growing broccoli in pots.
You can use commercial fertilizers, but it is easier to over-fertilize your soil with this option as they can contain too much nitrogen and can cause harm to your crops.
You can start your broccoli from seeds. If weather conditions are too harsh, you can start cultivating your seeds indoors. Do so around the middle of August and try to maintain a temperature of 75 to 80°F degrees.
Sow 3 broccoli seeds directly on your container 3 inches apart if you are using a 20-inch container. Cover them with ½ inch compost and water them well with the use of a fine-holed watering can to avoid washing out the seeds.
Choose the best seedling by picking out the weak ones after 4-6 weeks. If you are using a bigger container that is 5 feet across, thin the seedlings by leaving 18-24 inch space between them. Harden the seedlings by exposing them outside for 3 hours each morning for 2 weeks before you transfer them outside.
You can start your cultivation outdoors by planting broccoli seeds 4-6 weeks before the average last frost in your region when growing broccoli in containers. This will give you enough time to produce a good spring harvest.
Others recommend starting your crops with transplants as they form established plants much faster compared to starting from seeds. However, you do have the danger of buying a transplant that has clubroot, so choose carefully where you buy your transplants from.
If you wish to be sure, you can produce your own transplants that have been started indoors. Transplants are best planted outside in your container garden in early spring.
When you plant your transplants will determine when you will be able to harvest your crop. If you wish to have fall crops, have your transplants out in late summer.
If you have transplants with crooked stems for growing broccoli in pots, sow them in the soil by digging a hole that will reach up to the top of their first leaves. This will prevent your broccoli from becoming top heavy which is something to be aware of when growing broccoli in pots. One transplant is good for a 24” container.
If you wish to grow more in a bigger container, maintain a distance of 18-24 inches between each transplant. If you have started your transplants indoors, harden them the same way as described for seedlings.
Care and Harvesting
Always make sure to keep the soil moist but not wet, especially during warm weather conditions. Watering is also important when your broccoli starts to head. If outside temperatures reach up to 80 degrees, you may want to bring your broccoli to shade or indoors to keep them cool.
Keep away cabbage flies by placing pots of rosemary, thyme, or sage close to your broccoli containers.
This will aid you in lessening the number of chemical insecticides you use on your plants and can be pretty beneficial for organic gardening. Maintain your crops’ health by side-dressing your broccoli with mature compost or compost manure.
You can even use compost to mulch your crops to insulate the soil and prevent weeds. You will often see cutworms and cabbage loopers attacking your broccoli. Keep them at bay by hand-picking them or spraying the leaves with compost tea.
Aphids are also a problem when growing broccoli in containers. They can distort the leaves, branch tips, and flowers, resulting in the failure of your crops to produce heads. Once you see them, blast them out with the use of a garden hose.
You can even do your own homemade garden spray to deter these aphids by steeping garlic in oil. Mix the strained oil in water and mild organic insecticidal soap for effective and efficient organic pest control.
Harvest broccoli at 100-150 days if you have started from seeds. Transplants will be ready for harvesting in a shorter period, around 55-80 days.
Buds should be harvested while they are still tight and dark green in color. The central heads should be cut with 5-6 inches of stem still attached to it. Never harvest heads that have formed yellow flowers as they have already bolted and cannot be eaten.
Leave the base with several outer leaves for the plant to produce a second harvesting season. Follow these general guidelines and you will be successful in growing broccoli in containers.