When To Plant Out Broccoli

When to plant out broccoli depends on your climate and your goal for the harvest.
 
The best time to plant out broccoli is in the early spring for a summer crop, or in mid-to-late summer for a fall harvest.
 
If you’re wondering when to plant out broccoli in your specific region, the key is to avoid extreme heat, because broccoli is a cool-season crop that hates the hot summer sun.
 
You’ll want to plant out broccoli when nighttime temperatures are consistently between 40°F and 60°F, and daytime highs stay below 75°F.
 
In this post, we’ll cover the exact timing for planting out broccoli, how to read your local frost dates, and the signs your seedlings are ready to go into the garden.
 
Let’s dig into the details so you can nail that perfect planting window.
 

When to Plant Out Broccoli: The Ideal Timing

When to plant out broccoli is really about working backwards from your last frost date in spring and your first frost date in fall.
 
Here’s the simple rule: plant out broccoli seedlings about 2 to 3 weeks before your last expected spring frost.
 
Broccoli can handle a light frost, and even a hard freeze won’t kill established plants, so you don’t need to wait until all danger of frost has passed.
 
For a fall crop, you’ll want to plant out broccoli about 85 to 100 days before your first expected fall frost, counting from seed sowing, or about 6 to 8 weeks before that frost if you’re using transplants.
 
The goal is to have the heads mature when temperatures are cool, because cold weather actually improves the flavor and sweetness of broccoli.
 

Spring Planting: Getting a Head Start

When to plant out broccoli in the spring is all about timing your seedlings so they hit the garden right as the soil starts to warm.
 
Aim to plant out broccoli transplants when the soil temperature is at least 50°F, which usually happens a few weeks before your last frost date.
 
If you started seeds indoors, you’ll want to harden them off for about a week before planting them outside.
 
This means gradually exposing them to outdoor conditions for a few hours each day.
 
Once you plant out broccoli, give it a good drink of water and consider a row cover if a late frost threatens, because young plants are more tender than mature ones.
 

Fall Planting: The Second Chance

For many gardeners, the best time to plant out broccoli is actually in late summer for a fall harvest.
 
When to plant out broccoli for fall depends on your growing zone, but generally, you’ll start seeds indoors in early July or sow them directly in the garden by mid-July.
 
Then, plant out broccoli seedlings in early August, or as soon as the worst of the summer heat begins to break.
 
The reason fall planting often works better is that the weather naturally cools as the broccoli matures, which is exactly what it wants.
 
You’ll also avoid the bolt-prone conditions of late spring, when a sudden heatwave can cause the heads to flower before you get a chance to harvest.
 

Signs Your Broccoli Is Ready to Plant Out

You can’t just pick any date to plant out broccoli; you need to check that your seedlings are actually ready for the transition.
 
The ideal seedling is about 4 to 6 weeks old, with 4 to 5 true leaves, and a sturdy stem about the thickness of a pencil.
 
If your plants are leggy or too small, wait a few more days before you plant out broccoli to give them time to bulk up.
 
Also, make sure the roots are well-developed but not root-bound in the pot, because that can stress the plant after transplanting.
 

Harden Off Before You Plant Out Broccoli

This is a step you absolutely cannot skip when you plant out broccoli.
 
About 7 to 10 days before transplanting, start setting your seedlings outside in a sheltered, shady spot for a couple of hours a day.
 
Each day, increase their time outside and gradually introduce them to more sun and wind.
 
Hardening off helps the plants build up a thicker cuticle on their leaves, which reduces transplant shock.
 
When you finally plant out broccoli, they’ll adjust to the garden much faster and suffer less wilting.
 

Watch the Weather Forecast

Another thing to check before you plant out broccoli is the extended forecast for your area.
 
You don’t want to transplant right before a stretch of heavy rain, because that can waterlog the roots and cause rot.
 
You also want to avoid a late spring heatwave, as temperatures above 80°F can stress the young plants and trigger early bolting.
 
The best day to plant out broccoli is a cloudy, calm day with mild temperatures, ideally in the late afternoon.
 
This gives the plants the whole evening to settle in before the next morning’s sun.
 

Best Practices for Successful Transplanting

Once you’ve figured out when to plant out broccoli, you still need to handle the actual planting correctly to give it the best shot.
 
Prepare the soil ahead of time by mixing in a couple inches of compost or a balanced fertilizer, since broccoli is a heavy feeder.
 
Plant each seedling slightly deeper than it was in its pot, right up to the first set of true leaves, to encourage strong root growth.
 
Space your plants about 18 inches apart in rows that are 24 inches apart, giving them plenty of room to spread out.
 
After you plant out broccoli, water them thoroughly with a starter solution that’s high in phosphorus to boost root development.
 

Mulch and Protect New Transplants

Mulching is a great move right after you plant out broccoli, because it helps keep soil moisture even and controls weeds.
 
A layer of straw or shredded leaves about 2 inches thick works wonders around the base of each plant.
 
Keep the mulch a few inches away from the stem to prevent rot, and you’ll also keep the soil cooler in summer and warmer in early spring.
 
If you live in a windy spot, put up a small windbreak or a cloche around each plant for the first week after you plant out broccoli.
 
The extra protection will reduce transplant shock and help your plants focus on growing instead of just surviving.
 

So, When to Plant Out Broccoli?

When to plant out broccoli comes down to your local climate and whether you’re aiming for a spring or fall harvest.
 
In the spring, plant out broccoli about 2 to 3 weeks before your last frost, once the soil is at least 50°F.
 
For a fall crop, plant out broccoli in late summer, around 6 to 8 weeks before your first fall frost, so the heads mature in cool weather.
 
Make sure your seedlings are 4 to 6 weeks old, harden them off properly, and choose a mild, cloudy day for transplanting.
 
With these timing tips, you’ll be enjoying big, delicious heads of homegrown broccoli all season long.
 
Now get out there and plant out broccoli at the perfect time for your garden.