Sharp sand.

[Gerry Webster]

Thanks Maggi.

I don't remember Ian saying the results were not encouraging.

Bulb log 34/05

[Maggi Young]

Well remembered, Gerry!  That log is here: http://www.srgc.org.uk/bulblog/log2005/240805/log.html

Yes, to start with he found that the bulbs needed extra feeding and he compensates for that now with more attention to  feeding through the growing season.
Bit more about sand and gravel here : http://www.srgc.org.uk/bulblog/log2007/210607/log.html


 To me it seems  like the "structure" of the potting mix remains more stable with the loam-less mix. If repotting is missed for a year ( or two!    ) then it doesn't deteriorate in the way that the "old" mix used to, when it would look very tired and dusty.

[gote]

Darren's description is very accurate. The sand must be dry of course otherwise it will stick in the sieves.
It is usually possible to buy sieved sand from the people who supply grit and sand for industrial use. They have it available in batches with minimum and maximum grain size. Unfortunately they want to sell it by the truck load. However, with a small donation to the "coffee funds" you might get a bucket or two informally. That is the way it works here anyway. the "sand" is quite often crushed rock so it is very sharp indeed.
Göte
   

[Gerry Webster]

 To me it seems  like the "structure" of the potting mix remains more stable with the loam-less mix. If repotting is missed for a year ( or two!    ) then it doesn't deteriorate in the way that the "old" mix used to, when it would look very tired and dusty.

Maggi - "tired & dusty" is a good description of my 2-year old JI based bulb mix. It could also be said of me in the middle of crocus repotting.  A fairly dispiriting experience this year; two very cold winters have not been kind to crocus.

[David Nicholson]

Maggi - "tired & dusty" is a good description of my 2-year old JI based bulb mix. It could also be said of me in the middle of crocus repotting.  A fairly dispiriting experience this year; two very cold winters have not been kind to crocus.

Same for me Gerry. I usually find when I'm re-potting that I get very chesty as result of the dust from running the old compost through a sieve to find the last of my very small Crocus corms. This year I bought a supply of face masks to use. It turned out to be a waste of money though, I put the face mask on and my specs steamed up and I couldn't see a thing.

[David Nicholson]

!. Buy the sand.

2. Buy an extremely accurate digital micrometer.

3. Buy a pair of fine nosed tweezers.

4. Use tweezers to place grain of sand in jaws of micrometer (remember to hold jaws of micrometer in a vertical postion or the grain of sand will fall off).

5. Adjust micrometer until light pressure is applied (don't overdo it or you might end up with 2 grains of sand).

6. Record measurement and place measured grain of sand in appropriate bucket. I'd suggest buckets for each 0.1mm grain size to ensure you get the results you want and hence good drainage control.

7. Repeat 4 to 6 until you have the required quantiy of sand of your chosen grade.

Please report back on your results as it will be of great assistance to your fellow forum members.

Memo to self: Never listen to advice from retired engineers

[Tony Willis]

I use builders sand for my plunge beds and the best sized bulbs such as crocus and corydalis and the quickest to reach flowering size  are those that self seed into it. It is heavy and wet but I have not plucked up courage to use it in my mixture.

[Gerry Webster]

So,how do I start to measure the grain size of my sand

I currently have two small bags of horticultural sharp sand which look very similar. One - J. Arthur Bowers -  simply claims to be "graded",  the other - Silvapearl - claims to be "3mm down".  Visual inspection suggests that the bulk of the Silvapearl is "down" which seems to be confirmed by the fact that most of it passes through a very fine sieve - a teastrainer.

[bulborum]

Maybe you can use Stainless-steel-window netting
I use 40x60 VMH crates with different holes

Roland

[Lesley Cox]

I use sand not so much for drainage purposes as my compost drains well anyway, but because roots just love it. Any plant will make new and healthy roots as it hits the sand, or so it seems to me. I use only sand for pots/trays of cuttings for instance. It seems to encourage the new, very fine hair-like roots.