Alpine house - to flag or not to flag!

[JohnnyD]

Clare & I are in the final stages of reorganising ourselves so as to have an alpine house.
After digging out around 3 tonnes of very heavy clay, (and deciding that the next stage can be carried out by a local professional!), I find myself at a loss to decide what to do on the ground inside the structure. (It's a Rhino 8' x 10' with extra vents.)
The benching will be double decker plunges in galvanised steel but should they sit, 'open bottomed' on the ground, or would it be better to 'seal' the underside, either by having complete boxes or for example with flags? (These will be manufactured 'in-house' so no detail design problems.)
In other words, while there will be a central path of flags - should they run under the lower plunges?
I can see the benefit of being sealed - easier to keep clean, no pest access etc., but would it be easier to control temperature and humidity if the lower plunges were open to the earth?
Any experience welcome.
J.

[ranunculus]

Hi John,
In my experience I would certainly prefer an essentially flat fully concreted area (with slight run off for drainage obviously), without any gaps around the edge or even weed-encouraging paving cracks. A simple drainage vent and channel would suffice to run surplus water away and the benefits of weed-free, slug-free, easy cleaning are equally as important as temperature control, etc.
Summer heat (that's a laugh, isn't it) can be tempered by splashing water liberally onto the concrete and the joy of working in the greenhouse without getting muddy, sticky boots is worth all the initial effort of pouring a two inch layer of concrete.
Sorry you weren't feeling well enough to join us for Monday's East Lancashire AGS group meeting - Tim Lever did us proud with a magnificent lecture on Yunnan. Hope you are feeling much better now?
Cheers,
Cliff 

[Paul T]

And if you're feeling really enthusiastic you lay heating pipes/circuits into the concrete floor, to aid in heating in winter if you're wanting it.

[JohnnyD]

In regard to heating - I am investigating the potential of a small refrigerator and TV set!
J.

[Paul T]

Hmmm... usually when one gets thrown out of the house by one's spouse it is to the dog house, not the alpine house!    Interesting new twist.  Sort of like sending your kids to their room for being naughty...... when their room contains a TV, stereo, X-box, books, videos etc.  hardly seems like punishment at all.

Or are you intending the TV and Fridge just for the plants to use?

[JohnnyD]

You know Paul - I never thought of that!
J.

[Peter Maguire]

Hi John,

I'd agree with Cliff - a solid concrete base would seem preferable and is what I installed when I put my alpine house up about 10 years ago. I reasoned that if there were going to be solid foundations for the plunges to stand on, then there wouldn't be much bare soil left anyway. I have deep, single deck plunges on brick pillars and floor area allows me to move plants in and out of outside frames depending upon the time of year; winter time it's plieones, cypripediums and arisaemas, during the summer the cyclamen live there.
The concrete is easier to keep clean than soil would be - it can be brushed down easily when the pots under the benches are changed over. If there is one thing that I would change next time, it is to skim the surface of the concrete with a plaster finish - the concrete surface is a bit rough.
Damping down is easily done with a hose, mind you I've only done it once this 'summer', although if you have deep plunges they can provide the source of the humidity. Temperature control is easily achived by removing panes of glass for the season, something I don't do enough of.

Peter

[annew]

I'd go for the wall-to-wall concrete option. We put down paving slabs, but there are always weeds seeding into the tiny gap between the frame and the slabs, which are the very devil to get at.

[David Shaw]

In our second greenhouse we laid a weed suppresant membrane across 2/3 of the floor and slabbed it. Easy to walk on and keep clean. The other 1/3 alongside the south side of the greenhouse does not have staging but a deep sand plunge for larger pots and taller plants.
I also have a beer fridge in the potting shed. It sometimes gets used for storing bulbs and seeds as well.

[JohnnyD]

Finally, the Grand Opening of our new alpine house.

Ceremony performed by the (almost) Right Honourable Algernon Peregrine Smethurst (known to his friends as Brian!), and his better half Shelagh.

Thanks to all who advised on foundations - aesthetics finally ruled in favour of flags - but with all joints thoroughly sealed.
Now all we have to do is learm how to use it!

[Diane Clement]

Finally, the Grand Opening of our new alpine house.

Ceremony performed by the (almost) Right Honourable Algernon Peregrine Smethurst (known to his friends as Brian!), and his better half Shelagh.    

The alpine house looks fantastic John.  I am sure it soon be the home of many (potential!) Farrer plants.   The floor looks good enough to eat the Pudsey Pig from.  Shelagh, where did you get that hat!  Wow! 
BUT is this the first time in history the Rt Hon Smethurst has not worn a tie for such an important occasion? Or is it hidden by the photo      

[shelagh]

My usually 'dapper' husband thought we were out or in for a relaxed evening of conviviality at the Dowers and so dropped his usually high standards.  As for the hat Di, I have to say both of them were provided by Clare and John in honour of the occasion.  I was holding on to mine for grim death as it was very windy/rainy, typical southern weather down there in Frodsham.

[Martinr]

Now that I've picked myself off the floor and had 3 stiff drinks to get over the sight of Brian without a tie I must congratulate John, not only on his magnificent new alpine house but on the extremely arty picture of Clare reflected in the first picture.

I wish you many happy hours of growing.

[Maggi Young]

I am in such shock at seeing Brian without a tie for only the second time, ever... that I am barely able to comment on the magnificence of Mr and Mrs Dower's very smart new alpine house!!
 I have resized the pix and repost them......

[mark smyth]

What was the source of the plunges?