Keeping your plants cosy in chillier weather when you've only been blessed with a small garden space is where choosing the best mini greenhouse can be your saving grace. After all, ordinary greenhouses are bulky, a little pricey and are best for gardening experts, who have sown a seed or two in their time. A mini greenhouse, on the other hand, lends a green thumb to the gardening novice, a beginner who aims to make their smaller outdoor space a little more welcoming with vegetables and flower beds in the hopes of seeing the UK’s wildlife.
During the warmer months, we are greeted by warm, inviting sunshine. Here, our beloved plants flourish, taking goodness from the sunshine and the water we gift them; all the while, they dig their roots deep into the soil and forage for nutrients. Around this time, we may turn to propagation, sowing seeds and taking cuttings. While it’s possible from a sunny spot indoors, says Geoff Hodge of Garden Answers, it’s far easier and more successful from a greenhouse.
Best mini greenhouse at a glance:
• Best mini greenhouse: Forest Georgian Tall Wall Lean-to Greenhouse – view at Shed Store
• Budget mini greenhouse: Smart Garden Gro-Zone 4-Tier Greenhouse – view at Robert Dyas
• Best mini greenhouse for tomatoes: VegTrug Small Wall Hugger Greenhouse Set – view at Dunelm
• Best mini balcony greenhouse: McGregor Garden Mini Balcony Greenhouse – view on Argos
Offering you essential outdoor storage, a growing frame or miniature greenhouse is, essentially, year-round protection for your plant nursery. If you’re growing new plants, herbs and produce for your spring and summer pots and planters or beds and borders, you’ve come to the right place. However, we don’t always have space in our gardens. A cosy spot for your greenery, a mini greenhouse provides light and warmth with UV protection – plus, it doesn’t take up much space.
From growing tomatoes to chillies, the best mini greenhouse will cater to your specific needs as a gardener. Whether you're a little experienced and require additional storage for your many cuttings or you're a keen beginner with a balcony, there are greenhouses for all. Rest assured, we’ve covered every aspect of these gardening powerhouses – with a buyer’s guide, FAQs nipped in the bud and many well-made miniature and smaller greenhouses below, hand-selected by us.
Best mini greenhouse
While a small greenhouse may not provide a great deal of crop, Geoff assures that it’ll help you experience “one of the best feelings in the world – the satisfaction of creating your own plants.” Conquer smaller spaces with the best mini greenhouses and grow houses for summer and winter, below…
Best mini greenhouse
Shed Storewww.shedstore.co.uk
The Forest Georgian Tall Wall Lean to Greenhouse is by no means mini - but, definitely made for smaller outdoor spaces (with its space-saving design). With a premium timber build and a fantastic 15-year anti-rot guarantee, this small greenhouse is constructed from a sturdy 12mm tongue and groove, making it strong and durable - not to mention stylish. Let's not forget the shatterproof styrene and automatic vents, which will help your nursery plants, herb garden or veg grown in optimum conditions.
Pros
- Made from pressure-treated PEFC-certified timber
- Stylish, shatterproof and space-saving design
- Features an automatic vent and two removable shelves
Cons
- May not suit all garden styles
Best mini glass greenhouse
Shed Storewww.shedstore.co.uk
Compact, this Halls Wall Garden 24 Small Greenhouse is the ideal small greenhouse for gardens. A lean-to option, the greenhouse has been constructed from rust-resistant, low-maintenance, robust aluminium. As expected, the glazing comes with horticultural glass and toughened glass is available as an extra. We would recommend upgrading. Complete with a smooth-action sliding door, this pick includes one roof vent with optional two-wire shelves. Pop on your patio or even your balcony.
Pros
- Robust, rust resistant, low maintenance aluminium frame
- Equipped with horticultural glass with toughening add-on
- Compact and ideal for smaller spaces and even balconies
Cons
- Not the most stylish pick
Best mini greenhouse for seed-starting
VegTrug / Dunelmwww.dunelm.com
For seed-starting, we recommend the VegTrug Nursery Greenhouse. An innovative high-quality greenhouse, it's made from treated and FSC-certified cedar wood. Adjustable, the shelves can be moved to help a variety of seeds and plants out. Plus, the included greenhouse cover allows for easy access for planting and harvesting; as well as this, it insulates produce or seedlings when cold. It's a special unit for staters and younglings.
Customer review: "Happy with this mini greenhouse as a lot stronger, good value for the price."
Pros
- Adjustable shelves depending on your requirements
- Reinforced PE cover can be used to create a growing station
- Suitable for any garden and for starting off seedlings
Cons
- Reinforced PE cover may not be as effective as horticultural glass
Budget mini greenhouse
Robert Dyas / Smart Gardenwww.robertdyas.co.uk
This Smart Garden Gro-Zone 4-Tier Greenhouse is perfect for smaller spaces and will give you a special spot to grow plants and flowers in a protective environment. Whether germinating seeds, propagating plants, growing and protecting vegetables, or extending the growing season, this grow house is lightweight but has a durable design - with adjustable shelving. With a reinforced PE cover and ventilation to protect your new friends, this is a budget-friendly, long-lasting pick for your crops.
Customer review: "Great little greenhouse, ideal for my needs, you can pack a lot on its four shelves and if you have a small garden it does not take up too much space."
Pros
- Easy access via the front zip-up panel, which fully opens and clips back
- Vent holes improve the airflow for a natural growing environment
- Simple in design and easily assembled without any need for special tools
Cons
- Reinforced PE cover may not be as effective as horticultural glass
Best mini greenhouse for tomatoes
VegTrug / Dunelmwww.dunelm.com
High quality and durable, the VegTrug Small Wall Hugger Greenhouse Set has a zinc powder-coated steel frame and includes a PE greenhouse cover and micromesh cover for protection from harmful rays, frost and pests. Plus, this set can be easily assembled to fit a Small Wallhugger VegTrug. With heat retained, this set extends the growing season. Let's not forget the multiple zip openings, too.
Pair with the VegTrug Small Wall Hugger Planter for a special spot for your toms.
Pros
- High-quality multi-use PE cover for protection and insulation
- A tall height of 90cm accommodates taller plants like tomatoes
- Complete with multiple zip openings for easy access to crops
Cons
- The planter (pictured) is sold separately
Best wooden mini greenhouse
Shed Storewww.shedstore.co.uk
The Forest Wooden Small Mini Lean To Greenhouse has two opening lids and two doors for easy access. It offers ultimate flexibility and style - for all gardens. Designed to trap lots of sunlight and warmth to extend the growing season, this compact pick should help you grow your favourite veggies with no sweat. With two internal shelves and a base designed to fit a grow bag, this pressure-treated greenhouse will help nurture your seedlings and younglings into fully-fledged plants.
Pros
- Offers the ultimate flexibility and style when space is at a premium
- Designed to trap the maximum amount of sunlight and warmth
- Pressure treated therefore offers a 15-year anti-rot warranty
Cons
- Not ideal for tall plants, such as tomatoes
Best mini greenhouse for style
Dunelmwww.dunelm.com
With a hinged lid and two doors, this Timber Cream GroZone Greenhouse has easy access to the three shelves, designed to store lots of plants. Made from FSC Certified timber, this mini greenhouse is ideal for seeds, plants, fruits and vegetables. Simply extend your growing season with this garden buy. Plus, it features a locking stay, so your precious veggies are kept safe. For easy gardening, the twin-walled UV-resistant polycarbonate glazing makes this a plant paradise. We love it.
Customer review: "Lovely little greenhouse but I’m really not sure the wood will last a winter… but looks great just now and doing a great job already."
Pros
- With a hinged lid and two doors, you have access to shelves
- Ideal for simply extending your veggie growing season
- FSC-certified wood and UV-resistant polycarbonate glazing
Cons
- Some customers are unsure if the wood will last
Best mini balcony greenhouse
Argos / McGregorwww.argos.co.uk
Keep your seedlings and young shoots safe from cold weather with this McGregor Garden Mini Balcony Greenhouse. It's perfect to pop on the balcony, patio or windowsill. For those of us with tiny outdoor spaces, this balcony greenhouse has been designed to help nurture indoor cuttings from your houseplants - or even look after herbs. It's an easy way to multiply and expand your collection.
Customer review: "My wife wanted something small to start off plant seeds rather than leaving them on the utility room window sill after I complained last year that I was constantly wiping the window sill and worktop to remove bits of compost. There is a sunny and sheltered spot where this small greenhouse can be left. It was easy to assemble and can easily be dismantled & repacked when out of season."
Pros
- Keep seedlings and young shoots safe from cold weather
- Perfect to pop on the balcony, patio or windowsill
- An easy way to multiply and expand your houseplant heaven
Cons
- PE cover is not as effective as horticultural glass
Best mini lean-on greenhouse
Shed Storewww.shedstore.co.uk
Perfect for year-round gardening on balconies or patios, the Palram Canopia Lean To Small Wall Mini Greenhouse has a sturdy aluminium frame and galvanised steel base. Plus, with the crystal-clear 4mm polycarbonate roof and side panels, this greenhouse provides 90% light transmission and UV protection. Easy access, rainwater runoff, and guttering make it a great choice for plant care.
Pros
- Rust-resistant aluminium frame and galvanised steel perimeter base
- The lid can be opened with props to control heat, humidity and airflow
- Provides the perfect conditions for plants to thrive year-round
Cons
- Not the most stylish pick
How we chose the best mini greenhouse
All of these mini greenhouses have been hand-selected by our team of Modern Gardens shopping experts. We carefully considered features, size and value in our selection of the best. Our team has spent hours investigating and researching mini greenhouses to make it easier for you to find the very best, and we'd never recommend a product we don't believe in.
Where possible, we also test and share the latest and best products you should know about. And, with help from Modern Gardens Magazine, Garden News and Garden Answers, we share expert gardening knowledge to help you get the most from your product.
Verdict: Which is the best?
Our favourite is the Forest Georgian Tall Wall Lean to Greenhouse. It is by no means mini - but, definitely is made for smaller outdoor spaces. Stylish, robust and equipped for all plants, this pick is a great choice.
Mini greenhouse buyers guide
When shopping for a smaller or mini greenhouse, there are a few factors to consider. Thanks to Geoff at Garden Answers, we grow into detail about them below – in our greenhouse guide.
Frame material
No matter the style of greenhouse you go for, your first consideration should be what it’s made from, says Geoff. After all, something as ordinary as material can “affect cost, weight and heat retention.” Below, we have listed the four common greenhouse material types:
Wooden frames – may look lovely, but will need treating every few years, like our garden fences, points out Geoff. After all, wood is prone to rot, mould and weather damage, which is why a treatment is a must. Believe it or not, wood “retains heat better than aluminium, so wooden greenhouses remain warmer for longer.” Geoff recommends Western Red Cedar for reliability.
Aluminium frames – are cheaper than wood and require little maintenance. Result. However, is the thought of a metal structure a little boring to you? Well, Geoff suggests considering powder coatings, which can help your greenhouse blend in – or stand out. He adds: “Aluminium doesn’t hold heat as well as wood, but the thin glazing bars ensure better light transmission.”
Glazing glass – is heavy and adds stability, says Geoff – not to mention has good light transmission. However, it loses heat easily. And, perhaps the obvious, glass breaks – especially when stray garden debris smacks into it. Plus, it can crack in extreme temperatures.
Polycarbonate – unlike glazing glass, doesn’t break or shatter, Lightweight, this material has reliable light transmission, acting similar to household double-glazed windows. This makes polycarbonate greenhouses best for “retaining more heat and reducing heat loss in winter.”
Glass
Toughened (4mm-thick) is far better than the standard horticultural glass (3mm), says Geoff. If it happens to break, “it doesn’t form large shards. However, it is more expensive.” So, we’d recommend a greenhouse with thicker glass – but, be prepared to pay out a little more.
Base
For rigidity and stability, ensure the base of your pick has a rigid metal frame, says Geoff.
Ventilation
Ventilation is essential in summer to regulate temperature and reduce overheating. Adequate ventilation ensures plenty of fresh air for your nursery plants and cottagecore herbs. Plus, ventilation prevents the build-up of moulders and reduces any condensation in winter. As a general rule, Geoff says that “roof vents or windows should be the equivalent of 15-20 per cent” of the floor area. In addition, side vents help “regulate airflow” when used with roof vents.
Gutters
Though not essential for all greenhouses, gutters or downpipes can help reduce rot in wooden models. Plus, they allow you to collect rainwater in a trusty water butt, lowering your water bill.
FAQs
What can I grow in a mini greenhouse?
Thanks to the Royal Horticultural Society, we have some suggestions on what to grow in a mini greenhouse or cold-frame, year-round and seasonally. So, if you're wondering how to use a mini greenhouse for beginners, we have some clear, fuss-free advice. There's so much opportunity...
Spring/early summer – is the time to “harden off tender young plants, such as half-hardy annuals and vegetables.” Essentially, these plants need to be toughened up – or acclimatised to cooler temperatures, lower humidity and increased air movement before being moved outdoors. Mini greenhouses are the ideal halfway house between warmth and harsh conditions.
Late spring/summer – bring extra warmth for tender summer crops, such as aubergine, tomatoes and chillies. Luckily for you, quicker ripening and larger crop means lots of hearty, veg-heavy meals sooner than expected. If you have the space, the RHS recommends propagating plants (semi-ripe cuttings, seedlings and growing-on) in some nutritious compost.
Autumn – brings a little cold in, with some unsettled weather and the first frost. During this season, mini greenhouses and cold frames are useful in protecting cuttings and young plants.
Winter – brings plenty of cold. Mini greenhouses and cold frames can be used to shield alpines from rotting and overwinter young annuals and other plants. You could add a layer of bubble plastic to the inside to provide a much-needed insulation boost against frost and draughts.
Year-round – support to grow a range of edible crops and other plants.
How do I build my own mini greenhouse?
Though many mini greenhouses are available to us, you can make one yourself, with popular methods involving bookshelves, plastic sheeting and wooden boards. We have found some do-it-yourself mini greenhouses for a budget-friendly solution, thanks to Garden Buildings Direct.
Remember to buy horticultural glass or polycarbonate for reliable light transmission.
Where do I position my mini greenhouse?
Each garden or outdoor space is unique, with its individual conditions.
That said, gardening retailer Thompson & Morgan says the best position for a mini greenhouse is in a spot with natural daylight. Ideally, a good amount of sun, but your greenhouse should be protected from harsh winds and frost pockets “to give your plants and seedlings the best chance.”
How do you heat a small greenhouse?
While a cold greenhouse can help with your crop yield, heating it will offer even more opportunities, says Geoff. A greenhouse heater is an extra blanket for your plants, crucial to combat cold and winter wet. An unheated greenhouse maintains an inside temperature that’s five to seven degrees Celsius warmer than outside.
However, by adding a little heat, your greenhouse may become frost-free – with even cool temperatures opening up “a whole new world of what you can overwinter and grow,” explains Geoff. Cooler temperatures can lengthen growing seasons in spring and autumn by a month.
Much like a conservatory, a warmer greenhouse helps you grow tropical plants in the UK. But, Geoff does ask us to be wary of the cost of heating a warm environment – astronomical, indeed. If you don’t want to heat the entire greenhouse, partition off a section for your tender plants.
There are three main types of greenhouse heaters: paraffin, electricity or liquid petroleum gas. You could even install solar panels if you’ve popped your mini greenhouse into a sunny spot.
Alongside heaters, you can invest in some horticultural fleece, which can be used for insulation or placed “over plants as a temporary covering to improve insulation when temperatures drop.”
Your chosen greenhouse’s retailer may offer secondary glazing, which we recommend since a winter garden can be bitter for plants. You may use bubble wrap as a cheaper alternative, but it “raises humidity and condensation, and reduces light levels.”
Though factors such as the type of heater, size of the greenhouse and outside temperature may affect how much heat output you will require, Geoff has calculated that roughly “1kW (3,400BTUs) gives frost protection for a greenhouse up to 8.4sq m (90sq ft) or gently heats one up to 3.7sq m (40sq ft).” As your greenhouse is small, you won’t spend as much money on heat.
What to read next:
Best large outdoor plant pots to give your plants space to thrive
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Piper Huxley is a Homes, Garden and Wellness Product Writer for Modern Gardens Magazine, an all-rounder. When she’s not writing about houseplants, she’s tending to her own growing collection…