AbleKay Posted December 10, 2015 possibly a dumb question but I'm game, assuming that not all moulds are bad for plant roots should I ignore this black stuff or give them a clean? i'd prefer to keep the pots chemical free is all, but don't want to harm my plants either so any recommendations (bicarb?) appreciated. thanks Share this post Link to post Share on other sites
Brendo Posted December 10, 2015 I'd imagine warm water & the scour side of a sponge will do the trick.. Just don't continue washing your dishes with the same sponge Share this post Link to post Share on other sites
plantlight Posted December 10, 2015 My clay pots look wore than that and I don't notice any effect on my plants. Clay pots are absorbent and stuff is going to grow on them. Share this post Link to post Share on other sites
Sallubrious Posted December 10, 2015 (edited) The mould is most likely harmless, but it's good practice start with clean pots so you don't transfer any pathogens to the next plant that will go into that pot. Acidified bleach kills almost everything - much more than straight bleach ever will. Mix 1 cup bleach & 1 cup of vinegar into 4 litres of water and scrub it with that. Wear rubber gloves and make sure you rinse off all the residue. It will outgas some nasty shit, so do it outside and don't breathe it in. Edited December 10, 2015 by Sally 1 Share this post Link to post Share on other sites
Strontium Dawg Posted December 10, 2015 Mmm, chlorine gas. Tickly. Share this post Link to post Share on other sites
Kykeion Posted December 10, 2015 You could always bake it in the oven. Just be sure it is bone dry. 1 Share this post Link to post Share on other sites
zed240 Posted December 11, 2015 Why don't you use hydrogen peroxide since it just breaks down into water and oxygen? Just be careful to wear protective gear as that shit burns. 2 Share this post Link to post Share on other sites
AbleKay Posted December 11, 2015 The mould is most likely harmless... that's all i wanted to hear they're new pots, just been sitting outside unused for 5 years so thought probably harmless to soil, plants kinda maybe. ...might just enlargen the drainage hole and spray with peroxide as suggested. that sounds like the easy way out thanks all Share this post Link to post Share on other sites
Evil Genius Posted December 11, 2015 You could try using a soil that is purely mineral and dries out faster. This type of stuff can only grow when the soil stay wet for a while. It´s definitely mold and I´d be more concerned about breathing it than it damaging the cacti. Most cacti will have no problem with this. But it´s not really healthy to keep moldy stuff around. So maybe dont bring it inside over winter. Share this post Link to post Share on other sites
_Cursive Posted December 11, 2015 Introduce Trichoderma and you'll have no worries. I've started using that on all my plants and that fungi is amazing at keeping the stress of plants down and helps remove harmful pathogens. Look into 'Rape cakes'. Rape seed based. Share this post Link to post Share on other sites