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10 messages
15/12/2012 at 14:14


I have recently acquired an allotment and want to increase the alkalinity of the soil for vegetable growing - the land is deficient after many years of being an allotment. I am manuring/adding compost regularly but wanted to know which of the following would be the best to use and what the differences are between them:

1) dolomite magnesium lime

2) hydrated lime

3) ground limestone

4) calcified seaweed




15/12/2012 at 15:17

Hi Cat, i can only comment on the seaweed part,being near to the sea almost all our allotmenteers use seaweed from the beeches,we use pillow protectors from the pound shop fill them with seaweed and place them in our water buts depending on how much we need,after 4 weeks( i do 8 weeks plus)  it makes just the best plant ,veg food there is and free , mind you it stinks ,we also leave it on top of our soil beds to rot in , this also is a great slug deterrent perhaps it's the salt content,none of us wash  the seaweed we just use it raw, we also store the seaweed in black bin liners as it also makes great potting stuff, you have to be careful not to use it too strong and the strength and use is already on this site ,and hopefully someone will explain how to go back to it there's lots of good advise given not too long ago so good luck Alan 

15/12/2012 at 19:49


Have a look at this web site!




15/12/2012 at 20:02

Hydrated lime is the one to go for, slugs, leatherjackets and wireworms hate it.

If you use just gypsum, it will improve the soil texture but not change the pH, best to do a soil test to see what you need.

whichever you use , dont over do as you could do more harm than good.

You need to put lime on alone, 2/3 months after manure and 1 month after fertilizer.

If you have already manured, put lime on in February.

15/12/2012 at 22:48

Alan,  I made feed from seaweed this year and have bottles of it left over, will it keep till the spring or do you make a fresh batch each year. 

16/12/2012 at 07:12

Just remember not to lime where you're going to grow potatoes! 

17/12/2012 at 08:47

Is that the same for gypum (builders lime ) Dove? as that doesnt alter the acidity just improves the soil.

17/12/2012 at 09:47

No, you can use gypsum on land where you're going to grow potatoes and it will help improve the soil structure, particularly if you're gardening on heavy clay, but as you say it won't alter the acidity which is Catattack's problem. (or rather his allotment's problem - I'd recommed Rennies if it was his problem ).

17/12/2012 at 16:52

Hi Zoom im told the older the better but im making every year due to the smell of the old stuff

Good luck

20/12/2012 at 13:13

Thanks for the responses. I will check the soil pH before doing anything. It just seemed weird that many sellers don't list which and when to use 

1) dolomite magnesium lime

2) hydrated lime

3) ground limestone

4) calcified seaweed

Merry Christmas 

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