[Grubbypaws]

What is the best food for my potatoes which are growing in bags?

I have googled it and am now confused. It seems that it should be a liquid food (why) but not anything with too much nitrogen; definitely not miracle gro which is what I have used previously!

One site says uses blood fish and bone once a month which is obviously not liquid. Another suggest a high potash food and yet another suggests tomato food once a fortnight.

To add to my woes another says be careful not to overfeed as this may damage the plants and says not to feed if you have added fertilizer to the original compost; which I did (chempak potato fertilizer)

 

So should I? with what? and how often? 

[mumofstig]

Blood Fish & Bone takes a while to release, so probably a bit late to be adding that to the bags, IMO.That's probably why the advice is for liquid feed, as it releases nutrients instantly.

John says

Once the bag is filled, feed weekly with a liquid tomato fertiliser instead of watering that day.

http://www.allotment-garden.org/vegetable/potatoes/growing-potatoes-bags-greenhouse/

[Goneterseed]

Tomatorite or equivalent will give you a high potash liquid feed as some do for tomatoes.
I use my own brewed comfrey tea and have been cropping Charlotte 2nd earlis for a week now.

[Grubbypaws]

Thank you! I think i am probably getting over complicated. Every other year I have used bog standard liquid feed and have had good crops although lots of foliage which flops over so less nitrogen and more potash is probably a good idea.

Should I treat earlies and mains differently; some sites suggest that mains have higher need for feeding? I have always treated them the same in other years.

I have some left over sulphate of potash. The mains are just flowering; would they benefit from a top dressing of this?

[Goneterseed]

I would say yes. You don't need to give the mains a higher dose, as they will get more over the longer period that they are in the ground.

[Salmo]

A good compost to start with should supply all the nutrients you need. All liquid feed will do is to grow bigger tops. I certainly would not add any more now.

Water is the key.

[Goneterseed]

Most composts will be exhausted of niutrients within about six weeks. Spuds are heavy feeders.
Watering will help the potatoes to swell but I prefer some flavour to them.

[mumofstig]

I agree, I give the ones in pots extra feeding as well 

[3759allen]

i only grow earlies in pots so no feeding needed as they don't need as much time, my containers haven't got enough room fo mains either really.

i use home mad compost with rotted rabbit manure in the mix, i then add a thin layer of rabbit manure mulch to keep moisture in. the rabbit droppings and mulch act as a slow release feed. but it does produce a lot of foliage, i find it hard to get a good crop with out excessive foliage in containers.