Thanks for the warning about roundup on my lawn,its a good job I didnt take a chance.

Hi Russwil, irf you really must grow rhododendron,s in your area, you really need to dig in loads and loads of peat, or ericaceous compost, garden compost, although acid , is not acid enough for these, and feed with sequestrine, Derek.

There are now about 4 different rhododendrons available which are said to be okay on alkaline soil. However, you've already got them growing - try watering with Sequestrene Iron Tonic once or twice a year, follow the instructions on the packet. I note that Murphy now makes a granular Sequestrene iron tonic plus feed product, said to work for months - better check the shelves at the garden centre, or check online to see which you prefer.
Do not, under any circumstances, use aluminium sulphate around your rhododendrons - some places still recommend it, and some people do too, but its toxic to rhododendrons.

Rotted manure is frequently alkaline and should not be used around ericaceous plants or shrubs. ine round your roses though!

Try Inkarho Rhoddos, They will thrive if you feed them regular.