I would like to use the above at 6% concentration to help improve the
oxygen capacity at the root level.I will be using a 7.5 litre watering can to
water my citrus in pots.It has been a problem for me,having rotting rots.
Anyone got any ideas how many tablespoons i should add to 7.5 litres and
how often should i water with this.Is it good for other plants like blueberries,
blackcurrants,pomegranite,chillis etc all in pots .Any advice appreciated.

I don't know anything about effects of H2O2 on roots of various plants, but I can help you with calculating concentration--first I need to know concentration of starting solution.

The concentration is 6 % in a 100ml bottle.My watering can is 7.5 litres.This
concentration is usually used to bleach hair.It is also available in 3% but i
thought why not get 6 %.Cheers

Do you have a target final concentration --in ppm or something--I do not know what would be harmful to the roots and what would be OK.

GarnetDragon posted this before. I bookmarked it but it won't come up.
"using H202 is beneficial for root rot." I hope Andi responds here.
Yes, it is used to bleach hair, but I know nothing about that. I also know it it use to cleanse & disinfect injuries on animals or humans. It helps get rid of infections. I have also heard of adding it to water solution to help get rid of root rot... maybe 1 Tbls per gal water (?). I believe Gina has brought a plant back to life by diunking roots of ill plants into peroxide solution & then repotting & they did fine.
Hope someone helps me out here. I will say peroxide is finel
If you cut yourself.... pour hydrogen peroxide on it it to avoid infection.

Thanks for your help.I found a link that has provided some very good info in the post below

http://www.hydromall.com/happy_grower19.html
sorry the other one wasnt right.