The Ultimate Beginner’s Guide to Outdoor Greenhouses: Tips & Practical Advice

Plant parents everywhere want to protect their plants from scorching heat, heavy rain and unexpected weather changes, but everyone is aware of a simple all-in-one solution to most of their problems - an outdoor greenhouse. 

Simply put, an outdoor greenhouse is like a cozy shelter for your plants. Built with transparent walls to let the sunlight in and block harsh conditions, it is placed outside your house or residence. It is preferred by most gardeners for keeping their plant babies safe and helping them thrive. 

This video is sourced from Youtube@Epic Gardening

Beginners often look for tips and practical advice when learning about greenhouses, especially when deciding whether a small portable greenhouse or a walk-in greenhouse is the right fit for their space. It’s a great first step if your goal is to grow a healthy backyard garden. If you're new to this but excited to set up a greenhouse, look no further. Our comprehensive buying guide covers everything you need to know before choosing the best outdoor greenhouse, how to maintain it, and some key questions to help you decide if it’s the right choice for you.

Table of Contents 

• What Is an Outdoor Greenhouse? A Simple Beginner-Friendly Explanation 
• How Does an Outdoor Greenhouse Work? Understanding the Basics
• Which Greenhouse is Best for a Small Backyard?
• Outdoor Greenhouse Buying Guide: How to Choose the Best One
• How to Set Up an Outdoor Greenhouse and Easy Maintenance Tips 
• Is an Outdoor Greenhouse Worth It? Final Thoughts for First-Time Buyers

What Is an Outdoor Greenhouse? A Simple Beginner-Friendly Explanation

As the name suggests, an outdoor greenhouse is a structure that helps plants grow in a controlled environment when placed outside. They are typically made from materials like plastic or glass, which allow sunlight to enter while trapping heat inside to create a warmer environment for plant growth than plants grown in the open air. Some gardeners also prefer a heavy duty greenhouse with reinforced frames and thicker panels for improved durability.

Furthermore, a greenhouse shields your beautiful plants from elements, weather, pets and any danger, which is a common problem among beginners who aren’t fully aware of possible challenges that surface when raising plants in your space. 

Think of a greenhouse as a mini climate-controlled shelter for your plants. You can do numerous things within the limits of this structure; you can start seeds, grow vegetables, or keep delicate plants safe throughout the year.

Especially for beginners, it’s a great way to extend the growing season and have more control over how your plants develop, without needing advanced gardening skills.

How Does an Outdoor Greenhouse Work? Understanding the Basics

A quality greenhouse does more than protect your plants. It is carefully engineered to create the perfect environment for them to thrive. We have broken down how an outdoor greenhouse works in simple terms.

Absorb sunlight - Think of a greenhouse as your car parked in the sun. Even if it appears to be cool from the outside, the inside is warm. That’s precisely how the said structure works as well. The walls and roof of a greenhouse are made from clear materials like plastic or glass, to let the sunlight pass through easily. When the sunlight enters, it warms up the air, soil, and plants inside.

Trap heat - Once the heat is trapped inside a greenhouse, it can’t escape quickly. It is designed in such a way that the warmth stays trapped inside, keeping the structure warmer than the outside environment. For people living in colder regions, a greenhouse is necessary to protect their garden, especially when the temperature drops early in the morning or at night.

Maintains humidity- As well as keeping the temperature warm, a greenhouse also locks in the moisture, which is critical for the well-being of plants. However, too much heat or moisture can also become a problem. That’s why most greenhouses have vents, windows, or doors. You can open these to let fresh air in and allow extra heat to escape. This keeps the temperature balanced and prevents plants from overheating.

Offers protection - We couldn’t ignore the external factors that often pose a threat to plants. But a greenhouse significantly reduces the risks, some beyond your control, such as unpredictable weather, heavy rains and pests. This means your plants are less likely to get damaged compared to when they are grown in open space.

A greenhouse also allows beginners to start planting earlier in the season and continue gardening without waiting for the perfect weather, as it creates the ideal conditions. For people who are trying their hand at plant-keeping for the first time, a greenhouse makes it easier and more predictable.

Types of Outdoor Greenhouses: Walk-In, Heavy-Duty and Small Outdoor Greenhouse Options

There are three main types of outdoor greenhouses: walk-in greenhouses, small or mini outdoor greenhouses, and heavy-duty greenhouses. The right one for you depends on several factors, including your space, budget, and gardening goals. Here’s a clear, practical breakdown to help you decide, especially if you’re working with a small backyard.

Walk-in Greenhouse - This full-size structure stands tall and allows you to freely move around within its enclosed space. Seasonal gardeners with specific gardening goals prefer a walk-in greenhouse, which warrants some level of experience to be maintained.

Key Features

• Tall enough, usually 6 to 8 feet in height, to walk inside
• Comes with space for shelves, tools as needed for multiple plants
• Often includes ventilation such as windows or roll-up doors 

Best For 

• A walk-in greenhouse is best for growing vegetables like tomatoes, cucumbers, and peppers
• These are ideal for full-season gardening as the conditions within can be controlled
• They fit best in medium to large backyards. So space is vital

Pros

• Key benefits include more growing space and better airflow
• Supports tall plants better and is ideal for vertical gardening
• Easier to maintain the plants with plenty of space for you to walk around 

Cons 

• Only people with access to more space can have a walk-in greenhouse
• Typically costs more to set up and maintain than its mini version 

Small Outdoor (Mini) Greenhouse - For modern home owners with limited space, a mini outdoor greenhouse is the perfect choice. You can still indulge in gardening throughout the year without the need for a large space.

Key Features

• A mini structure is usually under 3 m² footprint.
• It doesn’t stand taller than 3 to 5 feet, so waking inside isn’t possible
• The design is often shelf-based and vertical rack style

Best For

• Ideal for seed starting and propagation
• Better suited for growing herbs, small plants and seedlings
• Fit best in balconies, patios or smaller backyards

Pros

• More space-efficient compared to the bigger structures and affordable
• Easy to move around and set up without professional help
• Ideal for beginners or urban gardeners with little to no experience

Cons 

• Mini greenhouse owners have to deal with limited growing height, so they are not great for tall crops
• They also produce less if you are planning to grow food
• Not the best option for full-scale vegetable gardening

Heavy-Duty Walk-in Greenhouse - This is a tougher and more durable version of the standard walk-in greenhouse. This is designed keeping serious gardeners in mind, who want a long-lasting and reliable setup. The frames are thicker and stronger, while the structure itself is big enough to move around inside the walls comfortably.

Key Features

• Heavy-duty greenhouses are taller than their counterparts, with an average height of 6 to 8 feet.
• They come with thick over/panels for better protection and insulation
• There are vents, windows, or roll-up doors for airflow
• You can count on the additional space for shelves, tools, and multiple plants

Best For

• Growing vegetables like tomatoes, cucumbers, and peppers
• For Year-round or full-season gardening
• Gardeners looking for a durable, long-term setup
• For backyards that are medium or large 

Pros

• Heavy-duty greenhouses are highly durable and weather-resistant
• They offer more growing space and better airflow
• Best to support tall plants and vertical gardening
• Become easier to work inside due to extra space

Cons

• They cost much more compared to basic or mini greenhouses
• Not ideal for small houses as they need more space to set up
• Takes more time and effort to assemble compared to the smaller versions

Which Greenhouse is Best for a Small Backyard?

If you are dealing with a limited space, which is less than 4x4 ft, we highly recommend going with a mini greenhouse.  Small backyards, which are common in modern homes and apartments, can still host a garden, as long as you’re only growing herbs and seedlings. 

Naturally, a mini greenhouse becomes a budget-friendly starter option. The small greenhouses are specifically designed for tight urban spaces and patios. Or, you can choose a small walk-in greenhouse if you can spare at least 5x5 feet or more. 

The latter choice allows you to grow vegetables and multiple plants, and this is a favorite among people who like working inside the greenhouse with a limited space to spare. 

While a mini greenhouse is a perfect starter tool for tight spaces and early growth of your plants, a walk-in greenhouse is a full growing system, which is best for serious gardening in all seasons.

Outdoor Greenhouse Buying Guide: How to Choose the Best One

Beyond just its size, there are more factors to consider when choosing an outdoor greenhouse that meets your needs. Here’s a simple guide to help beginners and experienced gardeners alike.

Pick the Right Size - When deciding on the type of greenhouse to purchase, consider your actual needs. If you are going to cultivate herbs or plant seeds and do not have sufficient space, such as just having access to a balcony, a small mini-greenhouse is a suitable option.

However, if you have a small backyard garden in which you wish to grow vegetables, a larger walk-in greenhouse is recommended. However, if you are an avid gardener and wish to cultivate all year round, a large greenhouse would be ideal.

Choose the Right Material - The choice of materials used for construction should be considered when selecting the right outdoor greenhouse. The reason is that the polycarbonate panels are reliable, durable, and have better thermal insulation properties compared to the plastic (PE cover).

Hence, polycarbonate is recommended for hot and cold regions because of its durability. However, for a novice gardener, it would be wise to use the plastic materials since they are cheaper and lighter.

Consider Frame Quality -  It’s equally important to consider the quality of the greenhouse structure, which is usually made of aluminum, steel and PVC.

Beginners prefer greenhouse with aluminium frames, which are widely known for their corrosion resistance and low maintenance needs. The steel structure is more resistant to wear and tear than other materials; however, it may require an anti-corrosive layer. The PVC structure is cheaper and lighter in weight, but less durable compared to the above.

Ventilation & Temperature Control - Ventilation is very important for maintaining your greenhouse in good condition. Proper ventilation will help avoid the buildup of excessive heat, thus minimizing the risks of disease transmission between plants.

The right greenhouse should have ventilation such as roof ventilators or windows that will ensure that excess heat can be released from the building.

Match it to Your Climate - Selecting an appropriate greenhouse will depend on the climate in the locality. If you live in a hot climate, ensure there is proper ventilation in addition to protecting the greenhouse from excessive ultraviolet radiation that can result in overheating of the plants. For cold climates, select insulating materials such as polycarbonate panels.

Ease of Setup - If this is your first time, then it would be wise to select a greenhouse that will be easy to assemble. This should include greenhouses that are easy to put up, such as a mini structure, because of their light structure and easy-to-understand instructions.

Always start small if you are new to gardening and then upgrade. Keep in mind that the best outdoor greenhouse is one that balances size, material and usability for your specific needs. 

How to Set Up an Outdoor Greenhouse and Easy Maintenance Tips

Here’s a simple 6-point guide to set up and maintain your backyard greenhouse effectively:

Right location makes all the difference - Place your outdoor greenhouse in an area with access to ample sunlight, ideally about six to eight hours per day. However, you should position the greenhouse out of direct wind and any trees that might obstruct the view and harm your plants.

Water and arrange plants smartly - Ensure that you position your greenhouse on level ground to make it stable in the long run. Your structure can be erected on soil, concrete, or wood, depending on the stability and flatness of your base. Consider drainage during this process so that excess water will not accumulate around the greenhouse.

Arrange your plants smartly - It is necessary to plant the plants in such a manner that there is sufficient space for their growth and there is free circulation of air, as overcrowding may result in poor growth and diseased plants. The plants should be watered regularly; however, care should be taken to ensure that the plants do not get over-watered.

Clean it regularly - You should ensure the greenhouse remains clean at all times for plants to thrive. Wipe or wash the panels of the greenhouse from time to time so that the light may penetrate and reach your crops efficiently. Regular inspection and cleaning plays a huge role in keeping pests from damaging your plants. Furthermore, eliminate dead leaves and weeds from the greenhouse, as they can obstruct the growth of healthy plants.

A well-placed, clean, and ventilated greenhouse, regardless of its size,  will keep your plants healthy and growing all year.

Is an Outdoor Greenhouse Worth It? Final Thoughts for First-Time Buyers

Outdoor greenhouses aren’t cheap. Even the most basic structure costs hundreds of dollars. Therefore, it’s natural to wonder -  is an outdoor greenhouse worth it? Yes, depending on what you intend to do in your garden.

If you thoroughly enjoy gardening and are willing to invest your time and energy in maintaining it, go for it. Although a greenhouse shields plants from environmental conditions, it needs attention and dedication in order to see your garden thrive. 

As far as the greenhouse value vs. cost comparison goes, the initial expense may be rather high. However, if used properly, the efficient plant growth definitely pays off. For beginners, it is recommended to purchase small outdoor greenhouses.

Outdoor greenhouses are effective when used properly, but beginners should watch out for common greenhouse mistakes like poor ventilation, overwatering, or placing it in the wrong location. Overall, an outdoor greenhouse can be a great investment if you use them wisely and match them to your needs.

An outdoor greenhouse can completely transform the way you grow plants, giving you more control, better protection to them, and a longer growing season. If you’re ready to get started, begin exploring different greenhouse options based on your space, budget, and goals using our buying guide. Make the right choice, where you start small and learn as you go. Your future garden will thank you! 

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