How to Grow Portobello Mushrooms – Complete DIY Home Guide

Have you ever dared to dream about growing portobello mushrooms at home?

Maybe you’ve seen some portbello mushroom grow kits or even a hydroponic mushrooms kit and fancied starting trying your hand at a portobello mushroom farming side business?

We’ve got some good news for you! Growing portobello mushrooms at home is easy and you have come to the right place.

Today at the Garden Bench Top, we are exploring all things related to portobello mushrooms.

You can expect to learn:

  • a step-by-step guide to constructing your own portobello mushrooms growing kit,
  • Choosing your substrate for successful mushroom crops
  • Mushroom Growing Kits vs DIY at Home – which is best?
  • frequently asked questions about growing portobello mushrooms

Why you should try Growing you Own Portobello Mushrooms

Before we get into the meaty part of the article, we thought it would be useful for first – time fungi farmers to understand the reasons and benefits of growing their own mushrooms.

Apart from the obvious financial reasons for growing portobello mushrooms for profit, many home gardeners derive many intangible benefits as well.

First and foremost – freshly picked mushrooms taste better.

grow portobello mushrooms at home
portobello mushrooms are a tasty addition to any dish

If you ask any home gardener (or anyone around the Garden Bench Top for that matter), one of the main reasons for growing your own food is the knowledge that you can provide for yourself – even if it is just mushrooms or herbs. There is something intrinsically rewarding about knowing you are eating food that didn’t come from a local grocer or store.

Add to that, the fact that you are helping to reduce your carbon footprint through reduced packaging and less waste, and its hard not to run out and begin your edible mushrooms growing journey today!

What is the Best Substrate to use for Growing Portobello Mushrooms?

Before you jump online to order your portobello spores, you are going to have to take one step back and think about the substrate (or growing medium) that you want to use for your portobello mushroom kit.

The great thing about portobello’s is they are one of the most flexible mushrooms that can grow on a number of different substrates.

Our favorite portobello mushroom substrate recipe is a combination of growing mediums that provides the mushroom spawn with the necessary nutrients for a successful flush of mushrooms. To achieve this, we use a combination of manure-based compost.

Check out the exact proportions for the portobello mushroom recipe in our substrate guide.

Growing Portobello Mushrooms at Home – Step-by-step Guide

In this section we are going to run through the steps for growing fresh portobello mushrooms indoors.

Materials Required

  • a water tight tray that is at least 8 inches deep (approximately 20 centimeters),
  • growing medium of choice (we recommend a 50:50 composite horse manure, compost soil mix),
  • portobello mushroom spores,
  • peat moss bricks, and
  • spray bottle.

Steps to Contructing your DIY Portobello Mushroom Growing Kits

In this section we will be laying out a step-by-step guide to building your own portobello mushroom patch.

Now let’s get into the fun part:

  1. Before you dive into the construction of the actual kit, we recommend getting your hands on some measuring equipment, like a thermometer and hygrometer (to measure humidity). Once you have these items, you will be able to confidently find a location around your house or garage where your portobello mushrooms will thrive.
  2. Place your tray in the space you have chosen to grow your mushrooms, and fill the tray with the compost manure mix. You should be aiming to fill your tray until it is approximately 2 inches from the top.
  3. Open you portobello spores and sprinkle evenly across the surface of the growing medium. Be sure to break up any large pieces of spores to allow the greatest surface area of contact with the substrate.
  4. Cover the mushroom spores with the peat moss that has been presoaked. Be sure to remove any excess water from the peat moss. Our goal is to maintain a moist environment, not water logged growing medium.
  5. Monitor your growing kit over the next 2 weeks to make sure the peat moss stays moist. You can mist the top of the growing kit with distilled water from a spray bottle.

Growing Portobello Mushrooms Outdoors (in the wild)

Okay, so let’s get one thing straight. When we say ‘in the wild’ what we really mean is cultivating mushrooms outdoors in your garden, but with natural elements and in natural conditions.

growing portobello mushrooms outside
growing portobello mushrooms outside

Here are the steps for growing portobello mushrooms outside:

  1. So if we are going to be harnessing the natural elements to help us grow portobello’s outside, you are going to have to time your grow cycle accordingly. Portobello mushrooms prefer a colder temperature range around 50 – 70 degrees Fahrenheit (10 – 20 degrees Celcius). This is the full range that the temperatures should sit at (from the nightly minimum to the daily maximum).
  2. With so many elements (like the weather) already being held to chance, we recommend placing the odds in your favor by controlling as many other factors as you can. This includes building a raised bed for your mushroom farm and filling it with pasteurized compost. In doing so, you will eliminate any unknowns that may begin to compete with your mushroom spawn for territory. You should aim to create a raised bed with a minimum of 8 inches of compost deep, in a shaded area of the garden.
  3. The next step is the exciting part – seeding the organic matter in the planting bed with portobello mushroom spawn. To do this, even spread the spawn around the garden bed, making sure to break apart any larger pieces of spawn. The goal is to give the spawn the best opportunity to spread and grow by exposing as much surface area as possible.
  4. Finally, cover the portabello mushroom spores with a layer of sterilized compost (approximately an inch deep). And now it is a waiting game. After 10 – 14 days, you should begin to see mushroom pins breaking through the surface of the soil. If you don’t see any pins appearing around this time, there is a simple check you can perform. Carefully clear some top layer of soil away and see if you can see thin, white threads spreading across the compost. This is called white mycelium and is the roots of the mushroom spawn. This is a good sign that your mushroom farm is progressing in the right direction.

Should I use a Done-For-You Mushroom Growing Kit?

Whilst we love to get our hands dirty with some DIY projects at the Garden Bench Top, we do realize there are some occasions where using a done-for-you mushroom grow kit is the preferred choice.

This is particularly so if you are just entering the mushroom growing space. Using a grow kit that has everything pre-mixed is a great introduction into growing your own portobello mushrooms. Nothing beats that initial excitement of seeing your first mushroom pin heads breaking through the surface.

Another situation where a pre-made growing kit may be more suitable is when you don’t have a large outdoor space or garage. This means just because you live in an apartment or unit with a small yard, you don’t have to miss out on your mushroom growing adventures. Simply order a compact grow kits with a spray bottle, and you’ll be eating delicious mushrooms before you know it.

Frequently Asked Questions – Portobello Mushrooms

portobello frequently asked questions

Can you Grow Portobello Mushrooms from Store Bought?

If you are keen to upcycle your food waste (something we always encourage at the Garden Bench Top), then we have some good news for you. You can actually grow your very own flush of portobello mushrooms from the discarded stems of the mushroom. We will preface this by saying, if you are just beginning your journey into mushroom farming, we would recommend using portobello mushroom spores, as your success rate will be much higher.

For those who are after a challenge, growing mushrooms from the stems is definitely achievable.

To achieve a successful crop, we recommend putting the odds in your favor by salvaging portobello stems that are at least 1/4 inch in diameter.

You will need to set up a DIY growing kit (similar to the one built above). You can use black plastic to help line the kit to maintain moisture and prevent excess light from penetrating in.

The trick is to ensure moisture, stable humidity and an ideal temperature range (65 – 75 degrees Fahrenheit). This allows the mushroom stems to release their spores and inoculate the growing medium. You will know you are on the right track when you can observe white mycelium consuming your substrate.

Do Portobello mushrooms need sunlight?

Portobello mushroom light requirements differ depending on the phase of the growth cycle.

During the inoculation phase (when the spores are growing over the substrate), sunlight is not required. In fact, your portabella mushroom growing kit should be kept in a dark space, away from direct sunlight and in a steady temperature.

However, during the fruiting stage, some light will help to trigger the mushrooms to grow. It is at this stage you can move the growing kit to a lighter space, that is still humid, but also has fresh air flow.

It is important to note, at no stage should the mushrooms be in direct sunlight for prolonged periods of time. This will dry them out, and they will not form proper batches of mushrooms.

Is it spelled Portobello or Portabello or Portabella or Portobella?

This question gets asked a lot from our readers, and rightly so! With so many variations of the word, it can become quite confusing.

To put a long story short, they are all the same thing.

Ultimately, the spelling of the word portobello, portabello or portabella is up to the individual. It is also influenced by the region that they have been raised.

We use all the terms interchangeably throughout this article. Just so we can be inclusive of everyone’s preferences.

Fun fact – the Mushroom Council uses the spelling “Portabella” as their preferred choice. So, if you want to follow the official institutions guidelines, it looks like the ‘a’ is the winner!

Are Portobello Mushrooms easy to grow?

If you have read this far into the our article about growing portabello mushrooms, we hope you know the answer to this question. If you ask this questions around the Garden Bench Top, you will receive a resounding YES!

With the step-by-step instructions (detailed above), some patience and husbandry for your porto bello mushroom growing kit, you’ll be enjoying your delicious mushrooms in no time.

Can you grow portobello mushrooms in coffee grounds?

Growing portobello mushrooms from coffee grounds is one of our favorite methods of mushroom farming.

There are a few things you need to know before you try this method.

  • the coffee grounds need to be spent (or used) coffee grounds
  • they must not be more than 24 hours old
  • you will need to use coffee grounds in combination with other growing mediums like straw or peat moss

Note, not all species of mushrooms will grow on waste coffee grounds. Fortunately portobella mushrooms are one that can. Check out our article about Growing Mushrooms in Coffee Grounds to learn our exact strategy.

Can you eat uncooked portobello mushrooms?

Eating raw portobello mushrooms is safe, however we would recommend at the very minimum giving them a wash and clean before doing so.

Ideally, we recommend consuming portobello mushrooms by cooking them. The heat will help to cook out any potentially harmful or toxic substances, as well as tenderizing the mushrooms that will deliver an intense flavor.

Our favorite is pan frying portobella mushrooms in some butter and fresh herbs. Simple is often the best.

What is the difference between cremini mushrooms and portobello mushrooms?

Even though these cremini and portobello mushrooms have different names (they don’t even sound the same), they are the exact same types of mushroom.

The only difference between the two is the stage at which the mushrooms were harvested.

Essentially, cremini mushrooms are plucked while they are younger and less mature than their older sibling the portobello mushroom. Their mushroom caps are smaller and less developed.

What Next?

Now you are honorary Garden Bench Top Experts in growing portabello mushrooms, what are you waiting for? The next steps are to get started on your mushroom growing journey.

We recommend reading our Guide on Substrates as that will help you decide which growing medium is suitable for you.

If you still have questions about growing portabella’s leave us a comment below, and we’ll be sure to respond the next time we see you at the Garden Bench Top.