This seems to be the part of the forum where we can discuss horticultural supplies like sulphur, moss, compost - so here goes:
I have heard that planting agaves, aloes etc., outside is best done in pure ballast (for drainage). However I have looked at a few builder's merchants and it is very confusing:
What grade of ballast is best ? (it seems to be availabe in 10mm and 20mm sizes) - and does it matter much what it's made of ?
Also... most photos of ballast on builder's merchants' websites show a mix that is mostly sand, with some stone. I don't want any sand in the mix at all, since it holds too much water
Does ballast always involve a mix of sand and stone ? If so then I think I should be looking for chippings or gravel of some sort. Again - any recommendations ? Thanks !
Ballast (for raised beds)
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General HTUK rules apply. This section is for tips, hints and discussion on growing that is not related to any specific group of plants.
General HTUK rules apply. This section is for tips, hints and discussion on growing that is not related to any specific group of plants.
- Dave Brown
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Re: Ballast (for raised beds)
Hi Francis,
All the ballast I have seen is mainly sand. I have the 20mm, but I put rough crushed gravel under it to add to the drainage. Sounds what you are after is crushed brick and rubble, but where you would get that from I don't know.
You have to be a bit careful of having nothing that holds nutrients, as I found Agaves grew far better in ballast with a sprinkling of JI No3, than just in gravel
All the ballast I have seen is mainly sand. I have the 20mm, but I put rough crushed gravel under it to add to the drainage. Sounds what you are after is crushed brick and rubble, but where you would get that from I don't know.
You have to be a bit careful of having nothing that holds nutrients, as I found Agaves grew far better in ballast with a sprinkling of JI No3, than just in gravel
Best regards
Dave
_________________________________________________
Roll on summer.....
http://www.hardytropicals.co.uk
Dave
_________________________________________________
Roll on summer.....
http://www.hardytropicals.co.uk
Re: Ballast (for raised beds)
I was also going to suggest John innes No3, with gravel added to it as john innes has grit added to it anyway which will improve drainage. I will be planting my agave's in that come mid spring time.
Re: Ballast (for raised beds)
Thanks very much. I try to work in a bit of slow release fertiliser anyway from time to time. It is easy to top up with a bit of JI, etc., as required - but harder to improve drainage unless it is there from the start.
Last edited by fgtbell on Mon Jan 17, 2011 5:56 pm, edited 1 time in total.
- Dave Brown
- Site Admin
- Posts: 19742
- Joined: Sun Jul 09, 2006 10:17 am
- Location: Chalk, (Thames Estuary) Kent, England 51.5N 0.3E
- Contact:
Re: Ballast (for raised beds)
San, JI on its own is nowhere near well drained enough, and would need at least 50% sharp sand/grit added, if not more. I use John Inns No3 as it is used at about 1 part per 200 or so. If you are using a much higher ratio it will be too strong for an Agave.
Best regards
Dave
_________________________________________________
Roll on summer.....
http://www.hardytropicals.co.uk
Dave
_________________________________________________
Roll on summer.....
http://www.hardytropicals.co.uk
Re: Ballast (for raised beds)
Thanks for letting me know Dave, i will get some sharp sand/grit to add to it, then. also may be add some perlite to it as well.