Broccoli Growing ProblemsGrowing Vegetables Last Updated On 11/27/2023
Broccoli is a super-healthy food that should be on your menu. This superfood has lots of beneficial vitamins and nutrients you need. In fact, it is one of the top nutrient dense foods.
For these reasons, it's advisable to always have some fresh broccoli for your family. The easiest way to achieve that is to grow your own broccoli in your garden. By growing broccoli in your home, you will ensure that the broccoli you bring to the table is always of the best quality.
It's therefore not surprising that so many people choose to grow broccoli. However, there are some problems and challenges all gardeners face when they try to grow this healthy plant.
Broccoli: Care and Potential Problems
There are some common tips and guidelines most people use when growing broccoli. Most of the time, broccoli is treated and grown just like cabbage. A great attention is made to grow broccoli as rapidly as possible. Also, it's important to give broccoli plenty of moisture during the growing season.
Another important thing to keep in mind is to feed this plant all through the season. For a start, broccoli should be planted in a bed amended with aged compost. It's also important to keep in mind that young broccoli is gentle and should not be subjected to frost. Only the older plants get hardy but the younger ones tend to be very gentle.
Here are some quick tips on how to grow broccoli successfully:
- When to plant? Keep in mind that broccoli is a cool-season crop. Therefore, it's important to plant it somewhere where temperatures won't exceed 80 degrees F. Make sure to plant it in an area with full sun in a colder climate, while warmer climates require broccoli to be planted in partial shade. It's also important to provide broccoli with well-drained soil rich in organic matter. You can add some aged compost to the planting bed before you plant broccoli. When planting, remember that broccoli can be sown directly into the soil in the garden. However, it's better to start it indoors, where it can be protected from pests and early fluctuation in temperatures.
- The best planting time. In order to ensure success, it's best to sow broccoli indoors about 6 to 8 weeks before the average last frost date in spring. You should set the plants outside about 2 weeks before the expected last frost. It's best to plant early, because the warm weather in late spring can cause broccoli to bolt and flower. On the other hand, too cold weather (below 50 degrees F) can cause broccoli to form button-like flower heads that will never develop. It's therefore best not to plant broccoli until the weather is settled. In case you want to grow it as a fall crop, make sure to sow it in the garden about 10 to 12 weeks before the average first frost in the fall. You can protect mid-summer planted broccoli from the heat by simply planting it between taller crops, such as corn or tomatoes. In the late fall, you may use floating row covers to protect your maturing broccoli from high temperatures.
- General care. In order to grow broccoli successfully, it's important to keep it evenly moist. Never allow the soil to dry out. In order to make broccoli grow strong, you may side dress it with some compost tea 2 weeks after transplanting it into the garden. After this, side dress your broccoli with some aged compost when the main flower head begins to form.
- Harvesting. Broccoli is ready to be harvested soon after the flower heads reach 1 inch in diameter. Once you harvested the main flower head, broccoli will produce side shots for about 3 months. If you want to have a sustained harvest, space the plants at least 24 inches apart during planting.
These are some of the basic tips on how to grow broccoli in your garden. However, there are also some common growing problems most gardeners face when growing broccoli. While broccoli is not a truly difficult plant to grow, there are numerous problems that can appear. In order to grow broccoli successfully, you need to know about these common problems and how to solve them.
There are several seedling problems you may encounter when growing broccoli.
Seedlings fail to emerge from soil. This problem usually means that there is a pest involved. The seedlings are eaten and the roots are tunneled even before the plants can emerge from the soil. The common culprit is cabbage maggot. This is a small, gray-white worm about 1/3 inches long. The adult form is the cabbage root fly, which looks a lot like a housefly. The flies lay eggs in the soil near the seedling. Maggots hatch and tunnel into roots, leaving brown scars or slimy tunnels. In order to get rid of these pests, you need to remove and dispose damage plants immediately. It's also helpful to apply some lime or wood ashes around the base of the plants. Another thing you can do is to time plant to avoid the insect growth cycle. It's advisable to plant a bit later, once the weather is drier.
Weak seedlings or seeds rot. This is usually a sign of damping off. The seedlings collapse and have dark, water-soaked stems. Damping off is a fungus that lives in the soil, especially in very humid areas. To minimize the change of damping off, it's important not to plant broccoli (or any other plant) in cold, moist soil. Always make sure that the soil is well-drained.
Seedlings are eaten near the soil level. This is a sign of cutworms. These are gray grubs, about 1/2 to 1/3 inches long. You will find them curled under the soil. They feed on stems, roots and leaves. To get rid of them, you should place a 3 inch paper collar around the stem of the plant. You should also keep the garden free of weeds. Sprinkle some wood ash around the base of the plants.
Sprouts fail to grow or die back. In case you notice bluish-black spot on leaves and stems, it's a sign of blackleg, a fungal disease which makes sprouts rot at the soil level. This disease is spread by cabbage maggots and cutworms. To get rid of this disease, you need to remove and destroy all of the infected plants. You also need to keep the garden free of plant debris. You may add some organic matter to the planting bed and make sure that the soil is well-drained. Another way to prevent this problem is to rotate crops.
There are many broccoli growing problems you may encounter even if you manage to grow healthy seedlings. As broccoli matures, it gets stronger and hardier, and it becomes firmly established into the ground. It is a sign that your plant is growing strong and healthy.
However, there are numerous problems your plant may encounter at this stage. This is particularly true for problems on leaves and flower heads. Here are some of the most common problems you may encounter:
Problems on Leaves
Yellow spots on upper leaf surfaces and grayish powder on the undersides. If your plants develop irregular yellowish to brownish spots on upper leaf surfaces and grayish powder or even mold on the undersides, it is a sign of downy mildew. This disease is caused by a fungus. To prevent this problem, you need to improve air circulation and keep your garden free of plant debris. Also, you may choose to plant resistant varieties and rotate crops.
Dull yellow leaves.In case the leaves become dull and yellow, and if they curl, it may also cause the death of the plant. This so-called "cabbage yellows" is caused by the fungus Fusatium soil. It infects the plants where the soil is warm and it's often spread by leafhoppers. To treat this problem, remove the infected plants and control leafhoppers. Also, make sure to keep your garden free of weeds, since they can harbor diseases. It's important to keep the soil evenly moist, but not wet. Make sure to rotate crops.
Yellow leaves and stunted plant. These symptoms, accompanied by small glistening specs on roots is a sign of root cyst nematodes. They are microscopic, worm-like animals that live on the film of water that coats soil particles. To prevent this problem, solarize the soil with clear plastic in mid-summer and rotate cabbage family crops.
Yellowish leaves, slightly curled with small specks. This can be a sign of aphids. They are small, oval whitish-green, pink or black insects. They are known to colonize on leaves. Aphids leave sticky excrement called honeydew, which can quickly turn into a black sooty mold. To get rid of them, use insecticidal soap solutions or remove the pests with a blast of water. You may also mulch with aluminum foil, which will disorient these insects.
Deformed leaves with whitish or yellowish spots. This can be a sign of harlequin bugs or stink bugs. They are black, with bright red, yellow or orange markings. Harlequin bugs are insects that suck fluids from plant tissue, which causes yellow and white blotches. You can handpick and destroy the bugs and eggs. You should also keep your garden free of weeds and crop residue, since these are the places where these bugs breed. Stink bugs are green or gray shield-shaped insects and they feed on fruits. You should remove the weeds and garden debris to prevent them from attacking your plants.
Partially eaten leaves. If you notice this problem, as well as leaves webbed together, it may be a sign of cabbage earworms. They are green insects with a light stripe and they are actually the larvae of a brownish-yellow moth with gray markings. Larvae are known to spin light webs. To get rid of them, clip off the webbed leaves. It's also important to keep the garden weed-free.
Leaves eaten and the plant partially defoliated. This may be a sign of blister beetles. They are slender metallic or gray insects. Use insecticide to destroy them, or you may handpick them. Keep your garden free of weeds and debris.
Large holes in leaves and skeletonized leaves. This is a sign of cabbage loopers or armyworms. Cabbage loopers are light green caterpillars with yellow stripes on the back. Armyworms are dark green caterpillars. Both eat leaves and destroy them. Use insecticide to get rid of them. Make sure to keep your garden free of debris and weeds to prevent these pests from attacking your plants.
Chewed and slimed leaves. This is the sign of snails and slugs. You can set beer traps to get rid of them, or you may hand-collect them during night.
Pale green leaves that wilt. You may also notice slimy rot on stems, leaves and head. This is the sign of the bacterial soft rot, caused by Erwina bacteria. Rot cannot be cured. You should collect and burn the infected plants. To prevent this problem, make sure there's good drainage by adding some compost and organic materials to planting beds. Don't over-water your plants and make sure to rotate crops.
Problems with Buds and Flower Heads
Only small, scattered heads form. If no mature heads form, this may be a sign that your young plant is developing heads prematurely. It often happens if the temperature falls below 40 degrees F shortly after planting. To prevent this, protect the young plants with floating row covers or hot kaps.
Young plants flower. If it's cold outside, it will cause the plants to prematurely flower and produce seed without forming heads. You can protect your plants with floating row covers to prevent this problem.
Plant stops producing heads or buds. You may also experience that the older buds flower. In order to prevent this, you should harvest heads regularly - at least once every 3 days. In case the buds are allowed the flower, the plant will stop producing new heads.
Plant flowers suddenly. In case of the warm temperatures (over 85 degrees F), the plant will start to flower unexpectedly and form small yellow flowers. To prevent this, plant earlier so your broccoli will mature before the heat. It's best to plant mid-summer for a fall crop. Keep in mind that broccoli matures in cold weather. You may also plant early-maturing varieties, such as Green Comet Hybrid, Spartan Early and Premium Early.
Swollen and misshapen roots. It may cause the plant to wilt. This may be a sign of Clubroot- a soilborne fungal disease. To prevent it from happening, keep the garden clean of debris and weeds. Remove and destroy all the infected plants. Since the Clubroot is often found in acid soils, make sure to add some lime in case the pH of your soil is below 7.2. Also, make sure to rotate crops for at least 2 years, and always buy transplants from reliable suppliers.
Stunted plant. This may be a sign of numerous problems. In case you notice worms tunneling into roots, it may be a sign of the June beetle larvae. Another possibility are the Wireworms. In order to prevent this problem, check the soil before the planting and you may also flood the soil in case the larvae are present. Remove the infected plants along with the surrounding soil. Keep your garden clean of debris that may shelter beetle eggs.
Photo credit: Ting Chen