Long term container plants

What's the best way to deal with these? I have a hydrangea, a fuchsia and an agapanthus all coming back to life after last summer. Should I have done something about renewing the compost by now/ Can I get away with just liquid fertilizer this year?
What's the correct procedure for the future?
Thanks

 

I thought just liquid feed was fine. But i'm no expert. In fact i've not even had anything live long enough to need feeding

 

Daisy, take off the top inch of compost and replace with fresh. As for feeding, the best way is to give a dilute feed every time you water.

 

Daisybelle. It is my understanding that you can keep plants in the same compost for two or three years or may be a bit longer, if you feed them as David says.

But compost is organic and will rot with time, and degrade into a very fine particle size, and you will eventually get problems with drainage. Consequently the advice that I have seen for long term container plants is to use rock or earth based material which won't degrade in the same way with time.

 

While doing the removal of the top inch of soil you could bury a few of those osmacote pellets around the plant.
It help if your like me and dont always remember to feed through the summer.
The packet tells you how many to use according to the pot size.

 

Thanks guys, I'll do that. How long can you just keep replacing the top inch for? Is the idea that eventually they'll need a bigger pot anyway?

 

Knock them out the pots split them start them off in several new pots, the hydragea start some cuttings when big enough replace the original plant you can split them but they are not as amenable to it as the fuchsias and agapanthus.

 

I've got 2 plants a camelia and a bamboo that have been in the same pots for 15 years. I have probably been lucky but I've done nothing more to them than water and feed them with phostrogen. The Camelia has been wonderful this year it's about 6 feet high and covered with white flowers.