An Essential Greenhouse Guide for Beginners UK
If you are a beginner or someone who is interested in getting some type of greenhouse, then our guide below will really help inform any potential buying decision that you might make. Below we have created a long and detailed guide to buying a greenhouse.
We have also included the best plants and vegetables that we would recommend for beginners to get you off to a great and successful start with your greenhouse.
This is a very long article and as such we have broken this into sections which you can view in the table of contents below.
Is it worth having a greenhouse?
Before reading any further, this is the most important question to ask yourself. Small mini greenhouses cost around £75 on average. For a larger standard 8 x 6 feet greenhouse you can pay £600-800 on average. At the high end you can pay a few thousand pounds, for a high end design.
None of these prices are cheap, so the question is what advantages does having a greenhouse actually give you?
The easiest way to think of this is to know that having your own greenhouse allows you to grow more plants and crops for a longer period of time. You can start those plants much earlier in the season and also increase the harvest period much longer as well.
Anyone who loves gardening will at some point get a greenhouse. You will also see many abandoned greenhouses up and down the United Kingdom.
We have listed the benefits of owning a greenhouse in more detail below. We have also listed below the disadvantages of owning a greenhouse as there are also some of those.
Advantages of owning a greenhouse
There are a number of advantages of owning your own greenhouse, even a basic one. Those are:
- You will have a longer growing season - you are no longer dependent upon the great British weather as you can heat and easily ventilate a good quality greenhouse
- Protection - You will be protected, and your plants will be protected from the weather and in the UK that is really important.
- You have many more plant options - you can grow many different varieties of all types of plants. In reality if you create the ideal conditions you can grow almost anything. The most popular things grown in a greenhouse are tomatoes, peppers, cucumbers, corn, vegetables, The most popular flowers are geraniums, petunias, ferns, orchids and chrysanthemums
- Pests - You don't have to worry about common garden pests though there are still a few you may have to deal with.
- Relaxation - It is a very relaxing place to be. There are few things more relaxing than pottering around in a well cared for greenhouse.
There are a number of disadvantages of owning your own greenhouse. Those are:
- Expense and running costs - Depending on which type you want, the initial purchase can be expensive. Glass is never cheap but clear plastic can also be used but that will need more maintenance
- Installation Costs - These can be expensive enough to install initially as they need a level surface. Making a good foundation is very important so usually this means digging a good foundation, hard core, a good weed preventing fabric and laying some flag stones.
- Maintenance - They all need some maintenance - from minimal intervention to weekly/monthly activity depending on the size and shape of the greenhouse and what you plan on growing
- Additional expenses - depending on what level you want to go to, it is likely that you will have to pay for some form of heating, increased watering capability and other items for the greenhouse (Warning - there are lots of greenhouse gadgets)
What Types are Available?
There are 9 different styles or types of greenhouse, and the main differences in each of these is the actual shape, size, covering and style. Traditional greenhouses use safety glass which makes them expensive. More affordable options use polycarbonate panels instead of glass, and other types of greenhouse use some type of polyurethane plastic sheets which makes them cheaper again.
- Traditional Span - this is the best known shape and the most popular option in the UK
- Dutch Light - this is similar to the traditional span explained above but it has sloping sides
- Mansard - Again a similar design to the traditional span except that a more curved shape is created by angling the rows of glass
- Lean to - this is in reality half of a greenhouse and the ridge leans against an existing wall
- Dome - as the name would suggest these are a dome shape which some people prefer
- Polygonal - They use octagonal shapes mainly and people will buy these for their visual appearance
- Conservation greenhouse - the most expensive as they use angled glass and double glazing. These will be £5,000+ depending on design and size.
- Mini Greenhouse - these can be free standing but are more popular as a lean to. You don't go inside these and all your work is done from the outside. These are the cheapest option with prices of around £25-£50.
- Polytunnel Greenhouse - These are also popular as they are affordable at around £100-£150. They are made from powder coated steel tubing, usually have an arch shape and are then covered with some type of UV protected polyethylene.
The best way of deciding which one you want is to visit somewhere dedicated to selling greenhouses and have a good look around. Ask them as many questions as you can. Almost always the greenhouse you pick will come down to how much you are prepared to pay, and the style that you prefer.
Glass greenhouses are expensive and typically start at around £700 and just go upwards from that. They will have a metal base and structure and should have toughened safety glass. Usually they will have a sliding door and some type of ventilation. They should also come with a long guarantee so look for around 10 years at least.
Cheaper options such as PE covered are also available as are mini greenhouses and polytunnels. These can cost around £100 for the tunnels, and £60 for a mini greenhouse.
For a full sized polycarbonate style greenhouse those typically cost around £400-500 and they will use polycarbonate panels. Like the glass ones they will also have ventilation and sliding doors with an aluminium base and structure.
What Sizes are Available in the UK?
The size will of course depend on the shape. However, we have listed the most popular standard sizes just below:
- Small greenhouse 6 x 8 feet
- Medium sized greenhouse 8 x 10 feet
- Large greenhouse 10 x 12 feet
The best way to think about greenhouse sizes is that they come in the following widths:
4 feet, 5 feet, 6 feet, 7 feet, 8 feet, 10 feet, 12 feet and 13 feet widths.
So you can buy something as small as a 4 x 4 feet and all the way up to 13 x 31 feet in length. You will not be stuck for a size.
Again door heights and widths vary with the actual size of your garden. Doors are usually 2 feet wide and about 5'9" high. The ridge height is on average around 6'9". These will vary on design and the greenhouse type.
Taller people should pay more attention to size as you don't want to be constantly hunched over by height restrictions.
Enough Space & Location
We like to deal in reality here for most amateur and beginner gardeners. Our recommendation is to position any one side of your greenhouse in a south or southwest facing aspect for best exposure to sunlight. In the perfect world the ridge of the greenhouse should run from East to West to get the most out of the sunlight.
For the average sized garden greenhouse though, they are virtually a square shape, so that rule is not that important. Larger commercial greenhouses will certainly benefit from the East/West rule, but for the vast majority of homes, one side with a South or South-West facing aspect is much more practical.
You are basically trying to get as much sunshine, for as long a period of time as you can into your greenhouse.
Ideally you need a level surface. Most gardeners use flag stones for the foundations. Always allow 6-12" inches outside the dimensions of the greenhouse base. You can then bolt the greenhouse frame to the flag stones. The vast majority of greenhouses come with an aluminium base which can be mounted to the flag stones.
Of course it doesn't have to be a cement base. As long as the foundation is solid and level is really all that matters. If the area in the UK you live in is susceptible to strong winds, then you really will have to find a way of anchoring the greenhouse down.
As well as having a solid sound foundation, you should also give consideration to some type of wind blocker or shelter. Have a look around your garden and try to find some shelter for your location. All greenhouses, even the very expensive ones, are vulnerable to strong winds.
We have seen the frames of aluminium greenhouses twist in high winds. As any good greenhouse should be properly anchored, really high winds will not be able to lift it, but the force may twist the frame. The only way to try and prevent this is by having a location that is fenced off, or partly protected by hedges, shrubs or trees.
Avoid any overhanging trees as falling branches can damage your greenhouse.
Ease of use and maintenance
Give a lot of consideration as to how easy it will be to access your greenhouse and also to maintain it. Putting it at the bottom of a garden may sound OK, but in the Winter months, the distance may put you off. We have never read any research about the distance from a house to the greenhouse. However, most gardeners agree that the closer it is to the house, the more likely you are to pay it a visit.
You can have a greenhouse in your garden or yard and it can still be very useful without any utilities such as electricity or water. That said, both water, heating and airflow is made a great deal easier if you can easily provide these.
Consider how you can get water and an electricity supply to your chosen location. Most greenhouse equipment needs electricity, such as heaters, lighting, grow lamps, propagators and automatic watering systems etc
Having an easy source of water also makes managing your greenhouse a great deal easier.
Most gardeners will want their new greenhouse to blend into their existing garden landscape. It is worthwhile trying to imagine what the greenhouse will look like when installed.
If you decide to start using a greenhouse, then there are a few accessories to consider. Greenhouses offer protection for plants and also help keep you out of the bad weather. They work best if they have some form of heating and also good ventilation.
There are many different types of these that you can buy. These include paraffin, Parasene, and tubular heaters. The tubular remain the most popular. The size required will of course depend on the size of the greenhouse. Ideally a heater with some sort of timer is always going to be the best choice.
Automatic Vent Openers
As well as needing heat, greenhouses also need air to circulate. Now that can be as simple as opening a window and letting the air in. Some greenhouse owners prefer an automatic vent opener. That means they can still control the circulation of air at certain times, They are especially useful if you are on holidays and away from the home.
These are known as drip irrigation kits, which cost around £15-£30 depending on what features you want to have. You will need a handy resource of water in or very close to your greenhouse.
It's always important to know the temperature of your greenhouse and a simple thermometer is a simple and effective method of doing that. These usually have digital displays and will show overnight temperatures and current temperatures.
There are so many of these such as bins, seats, staging, hanging hooks, plant holders, potting trays, started kits, solar lights, repair kits, etc.
What can you grow in a greenhouse for beginners UK?
If you are just starting out, then just keep this process really simple to begin with. You can quite literally grow almost anything inside a greenhouse. We would advise to start off with something easy such as tomatoes. These grow really well and at the end of the process you have a great, fresh tasting produce.
For some variety, cucumbers, peppers and chilies are also good crops to grow. As you start to gain experience, then we would highly recommend growing corn and aubergines.
You can of course start growing flowers and plants much earlier, either from seed, or bought as seedlings before you plant them out in your garden
If you are a beginner just starting out and not sure if a greenhouse id right for you, then why not start with a mini greenhouse. These range in price from around £25 and go up to about £50 so a much more affordable option.
They will have a tubular frame with 3-4 shelves and covered with plastic. These are easy to assemble and the door usually has a zip for opening and closing.
These are designed to stand up on 4 legs. However, that makes them very prone to the wind and the vast majority of buyers will find some method of anchoring them.
They are useful in small spaces or on a patio or deck and they do offer you the chance to grow plants and vegetables.
A cold frame is a wooden frame which is then covered with glass or polycarbonate of some kind. They are designed to help with growing small, ornamental and vegetable plants that require protection from weather conditions and pests.
In other words they let the sunlight in and keep everything else out. These come in a variety of styles and sizes depending on how much you want to spend. You can also easily make these at home with some wood and glass or polycarbonate or even heavy duty plastic.
When people use the word cloche, they may be referring to two slightly different things. There is a traditional glass cloche bell jar style which is popular, but there is also a cloche tunnel that can be covered with plastic or netting. This is better known as a grow tunnel which we have explained just below.
The traditional glass cloche is really designed to sit over the top of a plant to increase the heat and help it to grow, They will have a vent in them to ensure good airflow. They are designed for the over-wintering of herbaceous border plants.
The grow tunnel may also be referred to as a cloche but as you can see from the image it is very different in style and size. These are basically a set of hoops that are joined together. They are then covered by a heavy duty plastic or by a netting.
When covered with plastic they are designed to help heat up the ground for growing purposes. When they have netting that is usually to protect them from birds.
As you can see buying a greenhouse is a big decision. All gardeners who have the room for one will certainly own one. Almost always this starts out as a hobby and a desire to grow plants and vegetables the best way they can.
They can be expensive though and with the many accessories available they can get really expensive. They also need quite a bit of maintenance. They satisfaction that you get though is very high and for many buyers a greenhouse is a fantastic investment.
There are some cheaper alternatives to a full blown greenhouse. For beginners these are also worth trying especially if you are not sure about buying a greenhouse. They are all designed to help you grow and protect plants and they also deliver great results.