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How often to feed a rose in container? This is 'Iceberg'. I have had it for many years in a (small) 16" pot, but this year is in a bigger pot and doing very well. It is covered in buds and just starting to flower. I understand roses normally need feeding a powdered feed twice per year when they are growing in the ground, first in April, then later in June. But am I right that when grown in pots they should be fed more frequently? I gave my Iceberg its first feed in April. What ought I to do next? How ought I to feed it hereafter this year? Advice appreciated.
19 May, 2011
Answers
Thank you Drc726. So you feed in April, say early April. Then mid May to early June. And then again perhaps later in July? The rose fertilizer I bought does not have instructions for how to feed containerized roses, only for roses in the ground. Can Epsom salts be bought at Garden Centres?
(For some reason my camera and computer are flattening out images horizontally and obligifying them).
19 May, 2011
Yes thats about it Jonathan and rightly or wrongly I treat the same. Plain Epsom salts is cheaper in a supermarket as GC sell it in expensive boxes, I have added it each spring for over 30 years, I was told this by an old gardener when I had yellow leaves on my roses it a supplies Magnesium which the shrub may get short of. One other thing I do think that rose above needs a good prune to give you better shape and more blooms.
19 May, 2011
Surely you don't mean a prune now? Is that not winter work only? It was pruned much last January. It is fully in bud and about to flower. Do you think it should prune a bit after it has finished its first flush?
19 May, 2011
You are doing fine with this Jonathan .When each bloom has finished flowering then cut below it by about 4" just above an outwards facing bud to get more blooms.
19 May, 2011
I recall I was given some advice by David Austin roses a few years ago that roses can be summer pruned down by about a foot. Then they would bud up again to perform a second flush. I will do as you say with this and reduce by 4" or so. It is only a fairly small bush, half the size of my others. Its shape is rather loose this year. Many thanks.
20 May, 2011
I find with my bushes I do it all summer as each bloom finishes and they just go on flowering. If you look on the internet you can find diagrams of where/how to do it Jonathan.
20 May, 2011
Hi Jonathan Feeding: This is what the RHS says on container Roses they use up food reserves quickly and grow better if top-dressed each spring with a granular rose fertiliser. Additional feeding may be required as per the manufacturer's recommendations. Avoid feeding after August as soft growth may be damaged by cold winters.
But this is what I do - In spring I take the top layer of compost off and replaced with new I then feed with rose fertilizer the first feed I also I add a table spoon of Epsom salts. I feed about every 6-8 weeks adds up to 3 times a season.
19 May, 2011