Growing Broccoli: From Seed to Harvest

What if I told you that you could easily grow your own broccoli, right in your back yard? Okay, maybe that’s not that big a deal. But what if I told you that it just might be the best broccoli you’ve ever tasted?

Store bought broccoli has one advantage: it’s usually available any season you want it. But that doesn’t mean that it’s packed with flavor, that it’s fresh, or even that it’s going to be as healthy to your body as you might think.

If you want the nutritional benefits that you should expect from a power house veggie like broccoli AND a robust flavor that doesn’t need to be smothered in cheese to be edible, it’s got to be grown in your own soil. And it’s not hard to do.

We’ll show you how.

How To Grow Broccoli

When to Plant

Broccoli is a cool weather crop, so the best time to plant in the garden is early spring or fall after the summer heat has died off. It’ll thrive in 50-75 degree temps, but most varieties will bolt (go to flower) in sustained temps above 80 degrees. It’s best to start seeds indoors to get a good start.

Starting With the Seed

For summer harvest, you’ll want to start your seeds about 6 weeks before the last frost date for your region. For fall harvest, start your seeds 14 weeks before your first fall frost.

An easy way to start your seeds is by using Jiffy Peat Pellets because you can get many of them into a tray. You simply add water and watch the pellets grow, then place the seed into the peat at the top. Lightly cover the seed and then place under a light source in a temperate room. Broccoli needs soil temps that are around 50 degrees to germinate well.

The indoor growing setup we’ve used for the past 3 years is very basic, but it’s allowed us to start thousands of plants in our basement for little money. You can read about it here.

We place all of our seed trays under LED lights suspended from low cost shelving in the basement. No heat lamps and no heat pads needed. Just make sure you don’t over water the peat pellets, otherwise it will encourage algae growth and the seed may rot. If there is water at the bottom of the tray you know you have too much water.

Potting Up

It should take 5-7 days for broccoli seed to germinate. In another couple weeks the seedlings should have 2-3 leaves. Now it’s time to pot them up!

We use 4″ plastic pots for all of our transplants, but you can also use red solo cups with holes poked into the bottom. When potting up, it’s really all about choosing the right soil. Eventually we’d like to make our own soil, but for the last couple years we’ve been using organic soil with worm castings meant for garden vegetables. Spendy but works the best in our experience. Place the peat pellet inside the pot and cover with soil. The paper around the peat pellet will eventually break down, and it’s porous so the roots will push through without any trouble.

Water your seedlings well. They’ll need 6-8 hours of light a day until they’re ready to be transplanted outside, but don’t put them back under direct lights or you might burn your plant. Next to a bright window works well.

Transplanting Outside

Your plants should be ready to go outside in about 5-6 weeks after, as long as daytime temps are in the 50s and you’re past the chance of a hard frost. But before you put them in ground you’ll need to harden them off.

Hardening off plants is a simple process that allows your plants to get used to outside conditions. Remember, they’re still fragile little babies at this point and can easily be stressed. You’ll want to slowly introduce them to sunlight and keep them out of the wind until they get a bit stronger. I know, this part takes patience. But believe me, the last thing you want is to lose your plants after spending so much time caring for them, just because you were anxious to get them in the garden. Been there, done that.

Place your plants outside in the shade to start the hardening process. After a couple days let them have access to early morning sunlight, but put them back in the shade during the afternoon. Your plants are ready to go in the ground after they’ve been exposed to 8 hours of direct sunlight for a week and don’t show any signs of wilting or stress. Don’t forget to water them well during this period.

When you’re ready to plant in the garden, space your broccoli plants 18-24 inches apart in organically rich soil with a pH between 6.0 and 7.0. Some of the best broccoli we’ve grown came from our raised garden boxes, but we also grow in 20″ rows spaced 18″ apart out in the marketgarden.

Mulching and Feeding

Broccoli needs cooler temps to thrive. Inconsistent fluctuation in heat will cause your plants to bolt early or crowns to be small. You can offer your plants a few advantages by mulching.

Mulching with straw, shredded leaves and even woods chips will help regulate soil temperature, lowering soil temps by up to 10 degrees, even in the heat of summer. A thick layer (4-6 inches) of organic mulch will also allow the soil around your plants to retain moisture and keep weeds from germinating.

Broccoli is a heavy feeder, requiring lots of nitrogen, phosphorus and calcium. Most of the time you can offer a good balance of these nutrients by amending your soil with well composted chicken manure. Fish emulsion or alfalfa meal are also great sources of organic nitrogen, and bone meal will offer enough phosphorus to keep your plants healthy.

Whatever you do, we strongly recommend not to use synthetic fertilizers in the garden. Using commercial fertilizer found in the box stores will harm the beneficial bacteria in your soil that form a symbiotic bond with your plant roots and help keep the plant healthy.

Preventing Pests and Disease

When it comes to pests, here are the biggest culprits you’ll need to watch out for:

  • Rabbits – put fencing at least 3 feet high around your garden bed, or plant in a raised bed not easily accessed. You can try some of the rabbit/deer sprays on the market, but you’ll need to reapply frequently.
  • Flea beetles – these come out in the cool days of early spring when the soil begins to warm, but usually go away when it get hotter. They can do some damage to tender leaves, but usually your plants will recover if healthy. Using a floating row cover is the best way to keep your broccoli protected in the early stages of growth. If infested, you can use Neem Oil or Diatomaceous Earth, although we’ve never had to use either.
  • Cabbage Worms – These will infest your broccoli in warmer weather as your crowns start to develop. Early prevention is best, and covering your plants with row cover helps to keep the moths from laying their eggs. Planting marigolds around your broccoli seems to help as well.
  • Aphids – These little guys can do some damage, but luckily they are the natural prey for lady bugs. If you don’t have an abundance of lady bugs in your area, you can buy them and release them in your garden.

Broccoli is usually pretty hardy once established, but there are some common diseases to watch for:

  • Purple leaves – When you see purple leaves on your plant, it can be a sign that temperatures have been too cold or that your plant isn’t receiving enough phosphorus. If temperature isn’t the issue, then watering your plants with a little fish emulsion or mixing some bone meal into the soil around the plants will add enough phosphorus to give the plant the nutrition it needs.
  • Downy Mildew – This is a fungal-like water mold that will usually attack your plants during the seedling stage. It thrives in a cool, damp environment, and will cause discoloration of the broccoli leaves. The mold can live in plant debris from the previous gardening season, so planting broccoli in a different space every year is the best prevention. It’s also best to water your plants at the base to minimize water exposure to the leaves and to make sure your plants have plenty access to sunlight.
  • Leaf Spot – This is a bacteria that will form discolored spots on your leaves. Your plant will usually survive if affected by leaf spot, but you’ll want to dispose of plants after harvest since the bacteria can over winter in the soil.

Whether you’re facing pests or disease, your number one best defense will always be to make sure you are working with healthy soil with lots of organic matter. Eliminating synthetic fertilizers and chemical sprays and interplanting with a diverse variety of plants will create a rich environment for your broccoli plants to thrive in.


Your broccoli crown and florets are made up of tiny beads that are actually flowers. If you wait too long to harvest, these flowers (beads) will open and eventually go to seed (bolt). Once your crown gets to size, check daily for any sign of early bolting and harvest at will by cutting the thick stem at an angle with a sharp knife, several inches below the crown. Different varieties will produce different sized crowns, so check the information from your seed distributor to know when crowns are mature.

After harvesting, wash the broccoli and let dry, then put in the fridge to prevent wilting. Broccoli should store for up to a week in the fridge.

The plant will continue to produce side shoots, smaller florets that can be harvested for a week or so after the crown is cut. These will be as tender and delicious to eat as the crown and can be used in salads or frozen for fall soups.

Once the plant is spent, pull it from the garden and put in the compost pile or feed to the chickens.

There you have it! Flavorful broccoli. Healthy broccoli. Right from your back yard. Totally worth the time and effort.

What are you waiting for? Get your grow on!

Leave a Reply

%d bloggers like this: