My motivation for a greenhouse, locating a greenhouse, design considerations for a greenhouse and build details of my DIY greenhouse.
1. Motivation and Inspiration for a greenhouse
As a keen gardener all my life I didn’t need convincing of the merits of a greenhouse. Some 10 years back I made a poly hut which severed well until it succumbed to an unseasonably heavy winter snow. In fairness the poly covering needed replacing long before the snow did it for me! This was one of my considerations when looking for a replacement. Polytunnels (or in my case a small 8’ x 8’ hut) are a cost effective way to get plants under cover but it is recommended that the polythene film is replaced every 4 to 5 years to maintain good light levels for the plants. A consideration for me also was that the greenhouse would be in direct line of sight of the house so whatever about the effectiveness of a polytunnel for the plant it is not the most pleasing on the eye!
The next option up from a roll of polythene is polycarbonate sheet. Certainly this material allows for a more ‘traditional’ style of greenhouse and is generally clearer than polythene roll. It probably wasn’t really a consideration for me but after watching the video posted by Eli on ‘The Kitchen Garden with Eli and Kate’ in which she compares the benefits of glass over polycarbonate sheet I didn’t need any more convincing that glass must be my choice!
Ella makes some really good points in her video but the risk of panels ‘blowing away’ and the difficulty of cleaning were deciding factors for me. Watch her full video here – https://www.youtube.com/watch?v=SU9wxAOnLAg
When it comes to glass greenhouses there are a lot of ‘flat pack’ aluminium frame options to choose from. In my searches the two names that seemed to come up most frequently were Rhino Greenhouses and Halls Greenhouses (both made in Great Britain), some examples of what I was interested in are here:
There are a whole range of other cheaper options advertised, many of which seemed equally good, like this one from A1Greenshouses.com
A word of warning though! The initial advertised price for these greenhouses looks attractive but when you add toughened glass (a necessity in my opinion), a different colour frame and ventilation the price really shoots up. Also you need to factor in the cost of putting down a good base, if you don’t already have a sound level site.
However, there was a major issue to consider. They simply were not available! Whether it was due to the gardening boom brought on by Covid-19 lockdowns or the blockage of the Suez canal by the Ever Given I was receiving quotes of 16-20 week deliveries.
In my searches for a greenhouse I came across a bespoke greenhouse builder based at the foot of the Clwydian range in North Wales, Green Bug Ltd. (https://www.green-bug.co.uk/). Robin McGregor displays a treasure throve of fantastic greenhouses on his site that he has hand built spanning over 10 years. There are just dozens beautiful greenhouses to see but I particularly like his range of ‘small greenhouses’ https://www.green-bug.co.uk/small-greenhouses.html
Robin is a true master of the ‘Victorian’ style greenhouse and from watching his videos I was inspired to attempt my own Victorian greenhouse!
One final consideration was time. In normal times I would not have the luxury of so much time but with nearly 10 hours a week saved in car travel due to ‘working from home’ I decided to invest those hours in a project that would stand long after Covid is gone (hopefully!).
2. Location of a greenhouse
I found that there are many considerations when siting a greenhouse, particularly in a suburban back garden. I suppose starting at the extreme end there is hardly any point considering a greenhouse if you back garden is completely overshadowed and the only direct sunlight landing on your greenhouse would be at best an hour or two. I wanted to grow tomatoes and generally these need at least 6 hours of direct sunlight to grow well and ripen. However, in the practicalities of an established garden with existing structures and features it isn’t always feasible just to clear the sunniest spot for a greenhouse. Also shelter from wind and convenience of access are also considerations. Having some natural shading may be an advantage as it can prevent the greenhouse from overheating and damaging plants on those (rare) long sunny days.
Eli in her channel ‘The Kitchen Garden with Eli and Kate ’ gives a good overview of location in this video – https://www.youtube.com/watch?v=rLbphjcpVBs
Leaving aside ideal considerations I sited my greenhouse roughly where my old polyhut had been located. This location receives 6 hours direct sun from early morning and some dappled sun late in the afternoon.