Dwarf french beans in pots

[littlemoney]

Yesterday I planted out an experiment of late dwarf french beans which were 2-3" tall. I heard on the radio this morning it is possible to grow them in pots under cover as they don't need bees for pollination. The growing guide suggested a 45cm pot which I don't have. Can I use smaller pots and how many plants per pot.I have lots 4" pots and one 10" and some others somewhere in between these sizes.

I don't have a greenhouse and hope by leaving the pots outside and moving to the porch later will give me a late crop. I also have a cold frame.

Is this a feasible idea as I can dig the plants out tomorrow, not today as it's chucking it down with rain.

I know that beans don't tolerate frosts but how low can I let the temperature go down to before needing to provide cover?

[ameno]

Those beans should do fine outside still where you are. You don't need to dig them out and pot them up.

If you do want to grow them in pots, though, you might get away with the 10" pot, at 3-4 plants per pot. I wouldn't bother with the 4". Best to use a soil-based mix if you can.

As for cover, it depends what you are trying to achieve. The plants will survive as long as there is not a frost, but if temperatures stay too low for too long they will simply stop growing.

[littlemoney]

Thank ameno . I was hoping if the temperature dropped I could put them in my front porch where it would be warmer so they would grow for longer. I have found so JI compost which I thought I could mix with some peat based compost. The JI has some ants in it, they got into the plastic dustbin where the compost was stored. Can I still use it?

[Penellype]

I routinely grow french beans indoors in the spring to give an early small crop of beans. I put 3 seeds in a 6 inch (2 litre) pot and they grow ok. I use grow lights, but you could grow them outside at this time of year. I also grow them in 30 litre buckets (about 14 inches across) and put upto 6 plants in these. I should think your 10 inch pot would support 3-4 plants.

The compost with ants in should be fine for potting plants, but I would be very wary of bringing it in the house. Ants are very clever creatures and can sniff out anything sweet. I was once given some home grown potatoes by a friend and there were several ants in the bag, which I didn't notice. I put them on the kitchen floor, and found a couple of days later the ants had climbed the kitchen units and tiled wall and got into one of the top cupboards where there was a jar of mango chutney that was a bit sticky round the top. They were all over it.

[ameno]

Thank ameno . I was hoping if the temperature dropped I could put them in my front porch where it would be warmer so they would grow for longer. I have found so JI compost which I thought I could mix with some peat based compost. The JI has some ants in it, they got into the plastic dustbin where the compost was stored. Can I still use it?

Realistically, dwarf french beans usually only give a single flush of beans, anyway. They can be persuaded to give a second, but it's always much smaller than the first and of lower quality, and comes several weeks later. The first flush should mature just fine outdoors, and the second flush probably wouldn't mature in time even if you brought the plants into the porch, as by then the dropping temperatures and light levels would slow the plants down too much.

You could add the John Innes compost, but personally I would just dig a bit of soil out of the garden. You won't actually need all that much to fill some 10" pots with a 50:50 mix of soil and compost.