Getting the spacing right is one of the most common questions for new broccoli growers. If you’re wondering how far to plant broccoli apart, you’ve come to the right place for clear, simple advice.
Proper spacing is not just about giving each plant room. It directly impacts your harvest’s size, health, and quality. Crowded broccoli leads to competition for light, water, and nutrients, resulting in small heads and more pest problems. Too far apart, and you waste valuable garden space. Let’s get your spacing perfect from the start.
How Far To Plant Broccoli Apart
For most home garden varieties, the golden rule is to space broccoli plants 18 to 24 inches apart. Rows should be about 36 inches apart. This gives each plant ample space to develop a large, full head and a strong root system.
This spacing isn’t a random guess. It’s based on the mature size of the plant. A full-grown broccoli plant needs that 18-24 inch diameter to spread its leaves wide. These leaves are solar panels, capturing the energy needed to produce that central head you’re waiting for.
Why This Specific Spacing Matters
Ignoring spacing recommendations can lead to several issues. Here’s what happens when plants are too close:
- Smaller Heads: Plants compete for resources, stunting growth.
- Poor Air Circulation: Damp, stagnant air encourages fungal diseases like powdery mildew and downy mildew.
- Increased Pest Habitat: Tight quarters are perfect for hiding aphids and cabbage worms.
- Restricted Root Growth: Roots become tangled and can’t access enough water and nutrients.
Spacing Variations for Different Broccoli Types
Not all broccoli is created equal. While 18-24 inches is standard, you should adjust for specific types.
Standard Full-Size Varieties
Examples include ‘Calabrese’, ‘Green Magic’, and ‘Belstar’. These are the classic broccoli most gardeners know. Stick firmly to the 18-24 inch spacing within the row. They form large, single heads and need every bit of that room.
Baby or Sprouting Broccoli
Varieties like ‘Broccoli Raab’ or ‘Spigariello’ are grown for their tender shoots and small florets, not one large head. You can plant these much closer, about 8 to 12 inches apart. They have a different growth habit and benefit from denser planting.
Mini or Dwarf Varieties
If you’re gardening in containers or a small space, varieties like ‘Munchkin’ or ‘Small Miracle’ are bred to be compact. Space these 12 to 16 inches apart. Always check your seed packet for the breeder’s specific recommendation, as it is the most accurate guide.
Step-by-Step Planting Guide with Correct Spacing
Follow these steps to ensure perfect spacing everytime.
- Prepare Your Soil: Work in 2-3 inches of compost or well-rotted manure. Broccoli is a heavy feeder and thrives in rich, well-draining soil with a pH between 6.0 and 7.0.
- Mark Your Spots: Before planting a single seedling, use a tape measure and a stick to mark where each plant will go. For 18-inch spacing, make a mark every 1.5 feet along the row. This visual guide prevents crowding.
- Dig Proper Holes: Dig a hole slightly larger than the root ball of your seedling. This makes it easier for the young roots to expand outwards into the soil.
- Plant at the Right Depth: Set the plant in the hole so the soil level matches the level it was growing at in its pot. Burying the stem too deep can cause rot. Gently firm the soil around the base.
- Water Thoroughly: Give each new transplant a good, deep watering to settle the soil and eliminate air pockets around the roots. Consistent watering is crucial in the first week.
Spacing for Direct Seeding vs. Transplants
Your method of starting broccoli affects your spacing technique.
Using Transplants (Most Common): This is the easiest way to achieve perfect spacing. You simply plant your pre-started seedlings at the 18-24 inch intervals as described above. You know exactly where each plant will be.
Direct Seeding in the Garden: If you sow seeds directly, you will need to thin the seedlings. Sow seeds about 3 inches apart. Once the seedlings are 3-4 inches tall with a few true leaves, choose the strongest one every 18-24 inches and carefully remove the others. Thinning is essential—don’t skip it because you feel bad about removing plants.
Companion Planting and Spacing Considerations
Broccoli gets along with many garden neighbors, which can help with pest control and space efficiency. When interplanting, always respect the broccoli’s space needs first.
- Good Neighbors: Aromatic herbs like dill, rosemary, and mint can deter pests. Nasturtiums act as a trap crop for aphids. Beets and onions are compact and fit well between rows.
- Space Carefully: Avoid planting large, sprawling plants like pumpkins too close, as they will shade out your broccoli. Also, keep other brassicas (cauliflower, cabbage) at a similar 18-24 inch distance to prevent disease spread.
Common Spacing Mistakes to Avoid
Even experienced gardeners can make these errors. Here’s what to watch out for.
Mistake 1: Ignoring Mature Size. It’s tempting to plant tiny seedlings close together. You must visualize them at full size, with leaves spanning nearly two feet wide.
Mistake 2: Forgetting About Paths. Leave that 36 inches between rows. You need access for watering, weeding, and harvesting without compacting the soil or damaging plants.
Mistake 3: Not Thinning Seedlings. It feels wasteful, but leaving all direct-sown seedlings results in a crowded, unproductive patch. Thin early and decisively.
Mistake 4: Overcrowding in Containers. In a pot, give each broccoli plant its own container, ideally a 5-gallon size per plant. Don’t try to squeeze multiple plants into one planter.
Aftercare Tips for Perfectly Spaced Broccoli
Correct spacing sets the stage, but follow-up care ensures success.
Watering and Mulching
Broccoli needs consistent moisture, about 1-1.5 inches per week. Water at the soil level, not overhead, to keep leaves dry and prevent disease. Apply a 2-3 inch layer of straw or shredded leaves around plants to conserve moisture, suppress weeds, and keep soil cool. The mulch also prevents soil from splashing onto leaves during rain.
Fertilizing for Growth
Side-dress your plants with a balanced, nitrogen-rich fertilizer about 3 weeks after transplanting. This gives them a boost just as they begin their major growth phase. Another light feeding when the main head starts to form can support its development.
Monitoring for Pests and Disease
Good spacing improves air flow, which is your first defense against disease. Still, check the undersides of leaves regularly for cabbage worm eggs and aphids. Hand-pick pests or use an organic spray like Bt (Bacillus thuringiensis) if needed. Healthy, well-spaced plants are more resilient.
FAQ: Your Broccoli Spacing Questions Answered
Can I plant broccoli closer together for a bigger harvest?
No, planting closer will reduce your overall harvest. Each plant will produce a smaller, possibly inferior head due to competition. It’s better to have fewer, robust plants than many struggling ones.
What happens if my broccoli is already planted too close?
If they’re still young (less than 6 inches tall), you can carefully dig some up and replant them at the correct spacing. Water them well after moving. If they’re larger, it’s best to remove every other plant to give the remaining ones room. It’s hard, but necessary.
Does spacing affect side shoot production?
Yes, absolutely. After you harvest the main head, well-spaced plants have the energy and resources to produce abundant, tasty side shoots from the leaf axils. A crowded plant is often too stressed to produce many side shoots.
How much space does broccoli need in a raised bed?
In a raised bed, you can use a grid pattern. Space plants 18 inches apart from the center of one plant to the center of the next in all directions. This is called intensive spacing and works well in the deep, fertile soil of a raised bed.
Getting the spacing right for your broccoli is a simple step that pays off enormously. By giving each plant the room it needs, you provide the foundation for a healthy, productive garden. Your reward will be generous harvests of crisp, flavorful broccoli that you grew yourself.