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Sharp sand vs Grit/ horticultural sand

Just to see if grit/ horticultural sand can be substituted by sharp sand (for general building use) in my flower beds for a drainage ? As it is much cheaper than horticultural sand .

Many thanks !


  • TheveggardenerTheveggardener Posts: 1,057

    kaperna We have heavy dark grey clay here and that's what I use along with a cheap multi purpose compost and horse manure when I can get it. As you say it is cheaper that horticultural grit. Others might disagree so please wait for others to respond before you decide. 
  • JohnnypJohnnyp Posts: 71
    Hi , ive just started using 6mm grit  mixed through compost when I'm planting new shrubs etc in pots or in a border if they need to have good drainage .I purchased it at the quarry up the road and is very cheap to purchase,I just give it a wash off before I use it in the compost mix ,used it to plant daffodils and tulips back end of last year and put a layer of about 10mm as a top dressing to prevent weed growth.
  • DampGardenManDampGardenMan Posts: 1,054
    The 6mm grit that @johnnyp uses will give much better drainage than sharp sand. 10mm would be even better. Wash whatever you purchase as it may have come from a beach and contain salt.
  • WaysideWayside Posts: 845
    I thought Sharp Sand was a good idea, until I read about building sand scarcity, and the environmental destruction it causes.

    Perhaps ballast is a better choice, or some by-product shards.

  • K67K67 Posts: 2,507
    Having gardened on clay since 1999 I gave had yellow, grey and red clay and have used both sand and grit and researched pros and cons. Some advise that you have to add literally tons to make any difference!
    So I use the grit to put under bulbs a bag or 2 of builders sharp sand in a smallish area but it doesn't make much if any difference, 
    The best is compost, manure, leaf mold, composted bark dug in and used as a mulch.
    I have always dug down until I get clay and then dug that out and replaced with good soil. Now at almost 70 it's a bit beyond me so raised beds helped, still moved a bit of clay but was able to add good soil etc on top. 2nd year this year and everything in my small garden doing well.
    Happy digging....
  • JennyJJennyJ Posts: 9,564
    I've been told by a builders' merchant (who didn't sell horticultural sand just builders' sharp sand, so no financial interest) that builders' sand can contain salt depending on where it comes from, so probably best to rinse plenty of water through it before using as a soil improver. 
    Doncaster, South Yorkshire. Soil type: sandy, well-drained
  • hogweedhogweed Posts: 4,053
    I always thought horticultural sand was neutral and builders sharp sand had salt in it. I've used only horticultural sand in my heated bed in the greenhouse but if mixing in with soil, I've just used what comes to hand. To mix with heavy clay I think the bigger particle size the better so 6mm and above of grit should be even better than sand. The only other place I would use horticultural sand for definite would be on my lawn(?!). 
    'Optimism is the faith that leads to achievement' - Helen Keller
  • BorderlineBorderline Posts: 4,700
    Fine sand is not helpful to clay soil. They will just bind the clay into big blocks. Only dig in rough grit if you need to, but the best way is to keep adding bulky matter like compost. The grit is good putting under and around bulbs and to use in small areas or potted soil, but in the ground, it's not worth it.
  • BobTheGardenerBobTheGardener Posts: 11,391
    edited April 2019
    There is sharp sand (also known a grit sand) which is crushed rock (often mined and graded from glacial deposits) and this is fine to use in the garden and will improve drainage on clay, but not as much as 4-6mm graded grit, which would be better.  Then there is builders sand, which contains a lot more clay and has rounded particles (this is mined from seas and rivers, beaches, deserts and buried fossil deserts.)  This is not OK to use on clay soil and won't improve drainage (as often said, the soil will turn like concrete when dry!)
    Builders merchants sell both (sharp sand is used in making concrete and builders sand is used for making mortar, so it's important to ask for sharp sand.  I've never had any sharp sand which was salty (and yes, I do taste it!)
    A trowel in the hand is worth a thousand lost under a bush.
  • Mr. Vine EyeMr. Vine Eye Posts: 2,385
    I've been wondering the same thing and was actually very close to starting a thread when I spotted this one.

    Ive just run out of Grit and sharp sand. I bought bags of both from a garden centre when I made an alpine bed. The left overs lasted me a while for potting.

    I had a look at getting some more but it seems so much more expensive than I remembered.
    East Yorkshire
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