Container Gardening

Having started to prepare my containers/pots/etc. for summer planting I thought a bit of advice from my GC friends would be helpful.

What sort of mixture (soil/peat/compost do people use?
Do you add slow release fertiliser/ water retaining granules/other?
When do you start fertilising on a regular basis and with what (liquuid fertiliser/other)

I recognise that this covers a lot of ground but I have some time - waiting for the frost to pass.

Happy Easter to everyone.....................

 

I think it all depends what you plan to grow in your pots, Barnaby. And what size the pots are .
Please come back and tell us.

 

Hi Barnaby.

It took me quite a long time to realise that you can grow virtually anything in a container - as long as its big enough.

For all my seed sowing and container planting I use 2 parts of multi purpose compost and 1 part of sharp sand. The sand is for extra drainage. You could use perlite instead, but its difficult to get hold of and more expensive. I read about this mix a long time ago and it was later confirmed when I read a book by an American University Botany Department on experiments in growing from seed. This was their standard mix.

But there is nothing to stop you adding ordinary soil from the garden as well, which then turns it into a John Innes mix. In fact the soil will provide extra nutrients.

For ordinary pots I would use the above, and I tend to reuse last year's compost mix, though many people will disagree with that idea. If I am feeding regularly, my view is that it doesn't matter that I have used up the original nutrient in the compost. However over time compost will rot down and become much finer. Over three or four years it will become so fine that it will start to impede the drainage. Consequently the general advice is that for plants in long term pots, either replace the compost at intervals or (much easier) use garden soil, which won't rot down.

It will do no harm to add slow release fertiliser and water retention granules. However my view is that they are expensive and so I prefer to water and feed regularily, and keep the cash.

I am on clay, which has a lot of goodness in it, so I don't bother to feed the borders, but I do regularly (once a week) feed all my pots. Whilst the plants are green and growing I use a balanced feed like Miraclegrow, but when they start to flower (or produce fruit) I use a high Potassium feed - like tomatoe feed. But I would never buy a liquid feed as you are mainly paying for the water - I use Phostrogen or something similar.

 

I don't do a lot of 'container' gardening so, for sowing seeds or potting on I generally use a John Innes mixed with sharp sand. For 'ready bought plants' (a few tumbling tomatoes or bedding plants for baskets, tubs and random other containers), I just use multi-purpose compost and mix in a bit of slow release fertiliser as well, I tend to use water retaining granules only in hanging baskets (because of the expense really) but as Peter has said, I do feed ..... a lot.

I think the mistake some people make is in assuming that plants in a container, once filled with (say) bought multi-purpose, will be fine provided they just keep them watered, but reading the 'small print' on the bags, you often find the caveat 'feeds for 4 - 6 weeks' - of course, this depends on how many plants they've pushed into say a hanging basket (and of course, more plants means less compost). Bedding plants are one thing, you expect them to die off at the end of the season, but something more permanent or edible crops are going to need a lot more feed, especially if the container is one you can't readily or easily empty and refill.

 

I normally use containers and pots for decorative planting including : fuschias, pelargoniums, geraniums together with a few trailing plants like Bacopa/Verbenas and others.
The mix I use varies but I generally use a compost/manure base then a blend of last years compost plus some more fibrous material for water retention - occasionally adding water retaining granules and always slow release fertiliser.

The reason for my question which I know is a sort of regular 'thread' is to see if anyone has any other variants. I also am likely to put a large plant e.g. canna lily/dahlia/other in larger pots to create a bit of height.

Hope this answers your question Alice and thanks to Peter S and Fidgetsmum for their advice.........