Hydrated Lime

[JMCKG]

As far as I can see the use of builders lime(hydrated lime) can be used the same as garden lime, only in smaller quantities. Anyone have an opinion?

[Jay-ell]

If you cave any copper sulphate you can make Bordeaux Mixture - originally developed to make grapes taste horrible (by a French man who wanted to stop his neighbours stealing his grapes) but had the side effect of being antifungal.

Bordeaux Mixture--UC IPM

[Jungle Jane]

Rhs says to use smaller quantities & be careful of your eyes & skin irritation!
https://www.rhs.org.uk/advice/profile?PID=144
Hydrated lime (calcium hydroxide), sold for use by builders, can also be used. It is a fine powder, quick acting, but can irritate skin and eyes if not handled carefully.
The effectiveness (called the ‘Neutralising Value’ (NV)) is expressed as a percentage of the neutralising value of pure calcium oxide (which is caustic so cannot be used). The NV varies between materials – typical examples include:
Ground Limestone (garden lime) – NV 50-55
Ground Chalk – NV 50-55
Ground Magnesian Limestone (Dolodust) – NV 56
Calcified Seaweed – NV 44
Hydrated Lime – NV 70
Therefore, if you use hydrated lime, you will need much less than products containing calcium carbonate.
Liming materials are very finely ground so that they work quickly. Avoid any products with lumps, as they will take years to have any effect.

[Potstubsdustbins]

I know one allotment society that has a 6 ton lorry load delivered annually so yes it can be used.

As Jane says be careful, years ago I worked at ICI now Tarmac Tunstead quarry producing the stuff, it can be an awful irritant, especially if it gets in your eyes where it is damp.

[Snadger]

I use the brown magnesium limestone (dolomite) Apparently, it doesn't cause scab on tatties and is cheap as chips!