Runner beans as perennials

richardellis66

I understand that they are essentially perennial but frost prone. Mine are in a raised bed. Anyone had success just cutting back and letting them re-grow the following year? Maybe we'll mulched? 

Or know how to preserve the roots over winter ?

Busy-Lizzie

Mine have never survived in SW France when I have left the roots in the ground. Unlike dahlias.

Pete.8

If often find last year's plants have re-sprouted when I prep the trenches a bit late in Spring, but I pull them up to dig in compost to refresh the soil for the next batch

nick615

richardellis66  I agree with Pete's 'occasional' verdict above but IMHO the need for annual crops in different locations (so as to avoid any disease being left behind) will far outweigh any potential benefit from hoping the odd plant will reappear.  Again, I'd suggest that, unless you have no other option, a raised bed isn't the best site for a crop that needs large amounts of nutrition holding, moisture retaining material underneath.  In a sense, it is 'perennial' insofar as seed can be saved from each year's crop and, once you've found a variety you like, you can hold on to it for decades.  Nevertheless, it's a crop that personifies the motto 'Fail to prepare, prepare to fail'.

Pete.8

I agree for many crops, rotation is important, but I think less so with runners.
I've been growing runner beans in the same location for about 25 years with no problems.
They are also grown in raised beds.
I dig out a trench in the spring and put in a thick (8-10") layer of compost/farmyard manure and replace the soil. The beans go in about 8 weeks after.
I also grow a 2nd batch in another raised bed.
They do need more frequent watering being in raised beds but produce a fine crop.

Personally I'd not bother trying to re-grow from last years roots.
They've done their work and are likely knackered.
Also, runners store nitrogen in root nodules in the early stages of growth then release it when the beans themselves start growing, I don't know if old roots are capable of doing this efficiently.

Of course you can save seed and re-use year after year, so long as they are not F1 varieties which will not come true.

richardellis66

Pete.8 said:

I agree for many crops, rotation is important, but I think less so with runners.
I've been growing runner beans in the same location for about 25 years with no problems.
They are also grown in raised beds.
I dig out a trench in the spring and put in a thick (8-10") layer of compost/farmyard manure and replace the soil. The beans go in about 8 weeks after.
I also grow a 2nd batch in another raised bed.
They do need more frequent watering being in raised beds but produce a fine crop.

Personally I'd not bother trying to re-grow from last years roots.
They've done their work and are likely knackered.
Also, runners store nitrogen in root nodules in the early stages of growth then release it when the beans themselves start growing, I don't know if old roots are capable of doing this efficiently.

Of course you can save seed and re-use year after year, so long as they are not F1 varieties which will not come true.

Thanks for the great advice