Tarmac Sharp Sand.

nick.plant

Hello looking for good advise. I grow my carrots in containers, I have been told to add Horticulture sharp sand 50/50 mix. Can I use ordinary tarmac sharp sand, or does it have to be Horticulture Sharp Sand.
kind regards
Nick

Fairygirl

Most sand has a high salt content, so you'd be better to wash it all through thoroughly. 

I'm assuming the sand you mention isn't the stuff for building though - ie making mortar or concrete? 

nick.plant

Hi unfortunately, yes it is, builders sand, However, for all intents and purposes, horticultural sand is the same thing as sharp sand and is similar to builders sand and horticultural grit. These aren't exactly the same things, and regional variations abound, but they all can be used for the same purpose: to improve drainage, particularly in clay-like soil.

Fairygirl

Sorry - but builders' sand isn't any good for drainage in clay. It does the opposite 

Palustris

In all the years I have been using sharp sand from builder's merchants I have never found one with salt in it. Easy enough to tell, taste it or look for bits of sea shells. Otherwise  it is ok to use in soil mix. Just make sure it is 'sharp' sand not soft red sand.

Pete.8

I agree with @Fairygirl builders sand BINDS the materials together - so will hinder drainage

Palustris

Exactly. If it makes good sand castles then it is no use for adding to soil!

Fairygirl

That's interesting re the salt @Palustris. I was always led to believe it had a fair amount in it. I stand corrected  
Useless for drainage though, as we've all said 

Palustris

At the moment though you would be lucky to be able to get sharp sand at all. None of the local suppliers have any in stock at the moment. I usually get mine from B&M, but they have not had any for along time now.

Perki

I always use Sharp sand for the garden when planting bulbs and pots for plants that need extremely good drainage . Horticultural sand is sharp sand its just been washed to be free of salt ( pending where its mined from as palustris has mentioned ) and lime . 
Sharp sand is used for making concrete.  Builders sand ( usually reddish colour ) is for mortar for brick layering / rendering etc  no good for the garden its to fine of sand.  

Fairygirl

No, you're right @Palustris - I had a major problem when I needed to replace fence posts earlier this year and you couldn't supplies for love nor money. Mixing up concrete in the heat wasn't fun!