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How to Grow Broccoli? A Newbie-Friendly Guide to Growing Broccoli

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Broccoli is one of those super foods, an all-time favorite, crisp, nutritious vegetable that makes you want to always have it available. But you don’t want to keep having to go to the market to buy it. You want it fresh out of the garden. Who wouldn’t love to have broccoli ready at their disposal on the regular?

This particular vegetable offers a sharp distinctive flavor with many varieties to choose from, from the well-loved big-headed versions to the spicy Raab on to Romanesco and then you have sprouting.

There are certain kinds of broccoli that will focus on a main flower head with others that sprout much smaller singular florets. It’s so good by itself or you can dress it up with condiments or cheese. 

It may be a bit complex as a novice gardener to try to learn on How to Grow Broccoli from seed, but I’m sure we’re all up for the challenge.

How to Grow Broccoli
via Flickr

Tools Needed When Growing Broccoli From Seed

In order to grow broccoli from a seedling there are several supplies that you’ll need to have on hand:

  • Seedling starting mix
  • Seedling trays
  • Seedling heat mat
  • Soil
  • Water
  • Growth light bulbs
  • Liquid fertilizer (kelp)

Then as the seedlings grow and are ready to be placed in the garden, you’ll need:

  • Mulch

The basic steps that you’re going to follow in order to learn how to grow broccoli are summarized here briefly for you and then we will expand each step individually.

  • Use a high-quality seed starting mix and fill your seed starting tray.
  • Only place 1 to 2 seedlings in each cell or you will need to thin them out as they begin to grow.
  • You can either make a hole in the soil and place the seed in or you can put the seedling on top of the soil and push it down.
  • Cover the seedling over with the soil and softly pack it over to be sure that the soil is making contact with the seedling.
  • You should water the tray from the bottom in order to not disrupt the soil.
  • During the germination period, you want to keep a lid on top of the tray so the soil doesn’t dry out.

Now that you have an idea of the process, let’s break everything down for you.

How to Grow Broccoli from Seed

In order to start growing your broccoli from seed there’re some things you need to know about the vegetable first.

Broccoli is a brassica and belongs to the cabbage family of plants. Growing broccoli from the seedling can prove to be a bit arduous and time-consuming to a beginner, but overall it isn’t difficult.

Broccoli is very cold hardy and requires minimal maintenance. The best way to start seedlings if you live in a colder climate is with seedling trays or a seed-starting kit which is how we’re going to learn. Warmer climates will be able to plant directly into the garden.

Reading the seedling packet will give you the zones and what is recommended for your particular climate and area.

When To Plant Your Broccoli Seeds

There are going to be different growing requirements based on what variety of broccoli seedlings you purchase, so it’s going to be, again essential  to read exactly what the requirements are for the particular version that you get as far as the starting dates.

Typically, seedlings should get started inside your home approximately 4 to 6 weeks prior to the last frost. But if you are in a warmer climate area, the seedling can go directly in the garden once the soil becomes workable in the springtime.

How Deep Does The Broccoli Go In The Soil

For broccoli seeds you are to plant them two times deeper than the width of the seedling. They are really tiny, so that would mean approximately ⅛” to approximately ¼” deep.

Seedling Maintenance

After you have the seeds in the soil the maintenance process begins.

  • Germinating. The germination process in the trays will take approximately 5 to 10 days based on the warmth of the soil. If the temperature is warm it’ll go faster but if it’s cold it will be slower.
  • You can use a seed starting heating mat if you want the germination process to go much faster. This allows the soil to maintain heat.
  • Water. The soil needs to be watered consistently and evenly from the moment the seeds are planted. The seedlings won’t grow properly if the soil is either too wet or too dry. You’ll need to check the soil regularly for moisture.
  • Light. Seedlings grow best in full light and will need a grow light added as soon as they start to pop. It needs to hang just a few inches above and moves up as they grow. This light stays on between 14 to 16 hours every day. You can manufacture any kind of light fixture and use grow light bulbs.
  • Fertilize. Once you see the start of leaves, they need to receive food beginning with some type of a weak liquid fertilizer increasing in strength as they mature. Organic fertilizers can include liquid kelp.

Planting the Broccoli Into Your Garden

How to Grow Broccoli

Before the seedlings go into your garden from the seedling tray, you want to see the first several sets of real leaves. The seeds are extremely frost hardy and are able to go in the garden 2 to 4 weeks before the last frost of spring.

  • Hardened off. Seedlings need to be hardened off prior to planting outside. Over the course of 7 to 10 days when temperatures at night remain above 50 degrees, the process begins with taking the plastic cover off of the seedling trays and allowing an oscillating fan to blow over them inside for a few days.
    • Then take the trays outside and sit them in a shaded spot for a few hours. Each day you will expose them to more sun, longer times, and more elements until they are outside for a period of 24 hours and have experienced all typical conditions. This will condition them to be planted in your garden.
  • Spacing. You want to read your packet for the variety you have to know exactly how to space but the recommendation is approximately 12 to 24” apart as they need lots of room to grow and should not be overcrowded.
  • Location. Broccoli loves to eat and will grow best in soil that’s rich with organic nutrients where they can enjoy loads of full sun and consistently moist soil that drains quickly.
    • Once the plants are situated outside, you’ll want to assist the soil for the broccoli with worm castings or rotted manure or some rich compost as well as a good fertilizer prior to planting.
    • You also want to keep mulch around the base of the plant since broccoli likes the cool weather in order to keep its roots cool. The mulch will also aid in feeding the soil and plant as it breaks down.
  • Harvest. You need to harvest your broccoli when the buds still appear tight and green. If they have gotten big and are beginning to turn yellow, harvest immediately as they’re about to flower.
    • Each plant is only going to produce one head. A lot of smaller heads will pop after the main harvest which will usually last all summer long.


Learning how to grow broccoli from seedling can be a little daunting at first, but once you do it, it’s loads of fun with lots of different varieties to experiment with.

If you liked this article, let us know in the comments, and let us know if this growing method worked for you!

Recommend Products

1. Non-GMO Broccoli Seeds For Sprouting Sprouts Microgreens

2. Urban Farm Fertilizers All-Purpose Vegetable Fertilizer

3. 50 Cell Seedling Trays Extra Strength, 10 Pack, Seed Starter Tray for Planting