What wast products leave plant roots?

[Repeating Decimal]

I am posting this here because my new ISP does not provide access to active hydroponics newsgroups.

I just visited a hydroponics store to buy a large reservoir for my nutrient solution, a Texas controller. They told me to replace the nutrient solution every ten days in order to remove the waste products given off by the plants. I think that that is more labor intensive than necessary. I was thinking that I justreplace the nutrient whenever the conductivity drops below a certain level. I would also replenish used nutrient several times before disposing of it. I do dispose of it by spreading it on plants growing in the soil.

My question to the group is: What waste products do plants produce that leave by means of the roots?

Bill

[Pat Meadows]

I'm not objecting to your posting here.... but you don't need to get news from your ISP.

You can use a different news server - I do. It's *free* and details are available here:

old-timers, this is the former cis.dfn.de - German news server - with a new address.)

You'd just need to register and then tell your news program where to fetch the news.

Pat

[Pat Meadows]

PS - see my prior post about using a different news server.

Alternatively, your ISP should be willing to add the newsgroups that you want. Have you checked with them?

Pat

[simy1]

I do not know, but plants produce active chemicals at the rhizosphere (the root surface) that break down soil compounds into something plants can assimilate. I suppose they could poison themselves eventually, lacking the buffer capacity of soil.

[Repeating Decimal]

in article [e-mail], simy1 at [e-mail] wrote on 8/2/03 5:25 PM:

Hydroponic formulations are usually well buffered. In particular, they have a lot of phosphate and ammonium nitrogen.

Bill

[Pat Kiewicz]

That is probably because rec.garden.hydroponics was on a list of bogus newsgroups -- ones that did not go through the proper charter proposal, RFD and vote. This means the big news servers don't carry it. And I don't recall seeing a RFD (request for discussion) in the time since I last perused a list of bogus newsgroups. (It would be easier to start an alt.* group on the subject; rec.* groups have to reach a threshold of interest before they can be authorised, so not enough 'yes' votes and the proposed group will fail, even if 'yes' votes outnumber 'no' votes.)

Well, some people think one of the reasons for crop rotation is to avoid an accumulation of root exudates by any specific crop.

Plants do exude compounds from their roots. These root exudates can be alellopathic (toxic to other plants) or can be involved in the symbiotic relationship with mycorrhizal fungi or other soil microorganisms. These root exudates may be what makes some plants good companions in the garden while other pairings are disadvantageous.

Yes, they do exist and yes, it might be best to purge them from a hydroponics system at intervals, especially if you are growing a variety of different plants.