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Greenhouses- where to start?
myclayjungle
Posts: 162
We recently cleared a derelict garden, which had been overgrown 20+yrs. We now have a large shed and some raised beds but the rest is bare. Last year I grew corn, tomatoes, pumpkins, beans, potatoes, chillies, beetroot, yacon, Jerusalem artichokes, strawberries, raspberries and various flowers. Inside the house I grow ginger, kaffir limes and lemon grass. We have the space for a greenhouse 10ft x 14ft but depends if we get a lean to type or freestanding. I'm new to gardening so my questions are:
- What do you use your green house for?
- Is bigger always better?
- I've read multiple things about position and am still confused which spot would be best.
Any help, advice, thoughts appreciated.
- What do you use your green house for?
- Is bigger always better?
- I've read multiple things about position and am still confused which spot would be best.
Any help, advice, thoughts appreciated.
Coastal Suffolk/Essex Border- Clay soil
1
Posts
As for the GH, the usual ( unwritten ) rule is the bigger the better - once you start growing in there, it's surprising how much more space you wish you had
Where to place the GH really depends on the available space and also, to an extent, what you plan to grow in there. Similar for the choice between Lean to and free standing - what would best suit you and your garden space. It is often advised that the ridge runs East to West but that is not obligatory and again will depend on your location and what you plan to grow.
It may be an idea to put a pic on here and mark the options of GH sites you are considering to enable some advice.
As to what people grow in their GH, it varies over the season - growing edibles ( toms etc.), raising tender plants - the list is endless. Do you plan to have an electricity supply to allow heating or will it be a "cold" GH.
Hope some of the above will help you on your way and I'm sure others will also have advice/suggestions
We have a hexagonal one, and don't recommend this, as they will only take hexagonal shelving. A standard rectangle will give you more choice when it comes to staging/shelving. Our wooden shelving warped, metal is better. We use metal freestanding shelving from IKEA, not proper greenhouse staging, and that works for us. It also means we can easily empty the greenhouse once a year, to give it a good disinfection, without having to unscrew any shelving from the frame.
We mostly use ours to start off seedlings, and to harden them off. We find that by June/July, the greenhouse is too hot to grow most things. We used to grow tomatoes and chilli's in ours during the Summer, but it became too hot for them during heatwaves. Bear this in mind. Many plants will find it too hot in a greenhouse on a 30c+ day/heatwave. Only really heat loving plants can be grown in greenhouses during very hot Summers (pineapples, ginger, etc). We leave ours empty now during the Summer.
Ours is on a North/South axis, but I don't think it matters, as long as it gets a good 6-8 hours of direct sunshine a day. We have found that ours gets too much sun, and is too hot, due to climate change. We have to put shading in during hot spells, and it's a pain. Lean-to's tend to be smaller than freestanding greenhouses, so if you want to grow a lot, I would opt for freestanding.
During our first year of having a greenhouse, we assumed you are supposed to leave the door closed all year round. This creates a hothouse, which is too hot for most plants. Ours is almost permanently open during the Summer, plus we have automatic ventilation vents in the roof. If you can afford these, they are great, and don't need any power source.
https://forum.gardenersworld.com/discussion/1062487/greenhouse-advice-please/p1
The general advice is buy the biggest that you can afford. Also think about shading, the temperature can rocket and even with the door and vents wide open, you will definitely need to factor that in.
I use mine for stating and growing on seedlings. In the Summer it has things such as peppers and aubergines along with pelargoniums to give a bit of colour. Spring has pots of bulbs that come into flower quicker than those in the garden, and at the moment there are also pots of Sempervivum to protect them from the worst of the Winter weather.
Another thing to consider is a power supply. This will enable you to have a propagating bench with a soil warming cable on a thermostat in an enclosed, insulated bench. Not only can you overwinter tender plants but you can propagate cuttings and bring on early crops. Heating the whole greenhouse is of course an expensive option while a heated bench is much more economical. Power is optional of course and you can like many people, do very well without it. I didn’t have it for many years but when I finally hooked it up I regretted not having done so from the beginning.
It has a door at each end which provides adequate ventillation and the shading net goes on in May. You can get PTs with side flaps for extra ventillation.
Ours is unheated but winters here rarely get below -8C and then not for long. I use ours in winter to shelter my 3 citrus plants and the pots of cannas and trailing fuchsias and have some turmeric in the ground and some trays of last years seedlings and cuttings growing on. On wet days we leave one door open by day so th ehens can shelter and fossick in the dry.
In spring I plant some tomatoes, a couple of cucs and then chillies and basil. I have some metal shelving units with plastic covers from IKEA and use those for seed trays and to bring on seedlings. https://www.ikea.com/gb/en/p/hyllis-shelving-unit-with-cover-transparent-s99291745/ These give a bit of extra warmth, especially at night, and keep the hens out.