[JayG]

Next year will be just my third season with a greenhouse so I'm still working on how to get the best productivity from it.

I don't grow French beans outside these days as I've got limited space and don't really want French beans at pretty much the same time as runners, so am looking to try to get some early crops in the GH.

Soil will be 65L bags of compost on the floor, preferably the stuff already used for this year's toms (suitably enriched if necessary) - is this a viable idea and does anyone have any experience of how early it might be possible to start cropping, suitable varieties (dwarf or climbing) etc.?

[zombiepaw]

I think you can sow them in March in a Green House.

[Paul Plots]

I'd guess that it all depends on how much sunshine there is to warm your greenhouse and how frost-proof it is.

Sow a few indoors in late February for planting in mid March might work.

Climbing French Beans might be best if you can give them support - I would have thought they should give a heavier crop. Having said that I've had some huge crops from dwarf beans planted out "early" under two 3m long cloches on the plot but I am much nearer the equator than you JayG. 

[syks grower]

I am 10 miles north of Sheffield and sow 1 st week in March in the 2 foot square tubs sold at pound land.  I use old growbag compost to which add a handfull of Blood fish and bone plus a few chichen manure pellets.
I just keep greenhouse frost free and cover with fleece on cold nights
 I have done this for 2 years. From mid /end april  I move the tubs outside in the day and just put them in the greenhouse at night.  2 years ago got beens First  week in june but it was  early July before I managed any this year

I Do a few climbing french and runners this way

Hope this helps

[sunshineband]

I grow a variety of dwarf french beans called Speedy early in March, three seeds to a twelve inch pot, spread well apart.

They germinate indoors on the windowsill and then right away go down to the frost rfee greenhouse on the staging. They get covered up at night with fleece if the weather is really vicious.

Gives me a nice early crop about mid May,by which time they are outside if the weather is decent
 

[shokkyy]

I think French beans might be a bit tougher than we think they are. This year, as an experiment, I sowed my French and runner beans in pots in my unheated tunnel in April rather than in the house (I was getting a bit overcrowded). They were up inside 2 weeks and seemed completely unworried by the frosts we were still getting in May. They germinated in quite chilly temperatures and grew away very quickly into strong plants, so I don't think they were set back at all.

[8doubles]

You may have to teach any early bees to open and shut the greenhouse door .

[mumofstig]

French beans ( and peas) do not need any bees, they're self pollinating