[A Reyt Tayty]

I've just been reading up on growing spuds in bags.
In the ground it's generally recommended to space 30cm apart and 60cm between rows, or yeilds may be affected. Yet, some recommend that you plant two or even three seed potatoes to a planter which only has a circumference of say 18". Why is the need for so many in such a small space?
I've done both this year and the single spud planted in the ground has thrown masses more foliage than the multiple plantings in bags. I'm putting it down to overcrowding and fighting for nutrients in the bags, even though they have been well fertilised.

[mumofstig]

I think the reasoning behind it maybe - that usually you end with a greater depth of soil in the potato planters they sell, whereas in the soil they are usually planted nearer the surface, with just a little earthing up 

I think tubs are worth it for a few earlies or growing a few for show, but other than that I wouldn't bother again.

[Beetroot Queen]

I am not bothering with tubs again as harvests were rather poor, but i expect next year i will forget i said this and make the same mistakes 

[carlrmj]

   I managed to get a lot of one ton builders bags .

  I filled with weeds ( perennial and annual ) ,grass cuttings and covered with black polythene, then left for a few months .

  This was then topped with fresh soil and compost and I planted 5 potatoes per bag ( earlies ) , had loads off them ,with lots of foilage .
 

[Yorkie]

You tend to grow first earlies in containers, which are the closest spacing for spuds, but lower crops are frequently reported in containers than in the ground.  Feeding and watering are crucial.

[solway cropper]

I'm not a big fan of those planters but I do use an assortment of containers for my spuds from flower buckets to 17 litre polypots. I only put one seed per container and usually get 1 to 2 lbs of first earlies from a flower bucket but they are picked small. The polypots are giving me 5 to 6 lbs of Picasso per seed but there's still time for them to bulk up further.

[syks grower]

I always plant some first earlies in 18 " square planters in late feb in greenhouse.

I put two tubers in about 6" of compost when the tubers sprout i keep putting more compost in till I get to the top.

I find this helps to stop the plants flopping all over the place.

I harvest by scapping away some compost and only talking what I need this allows the small tubers to get much bigger

[Kristen]

Gardeners World as week or so back (or was it Beechgrove, I forget ...) tried 3 and 4 tubers in a conventional potato growing container.  Yield was identical, so conclusion was that 3 was sufficient.

I plant 3 tubers in the bags, and 4 in the somewhat larger "pots" that I also use. Although tipping them out gives quite a large harvest and we prefer to eat New Spuds shortly after harvest, so having a bigger container / yield somewhat defeats the object (unless you are tight for growing space).

I only use containers for spuds for earliest harvest, and planted again first week of August for a harvest around Christmas.