How do you produce different alkalinity and acidic properties in your potting soil?

Question

For a Schefflera plant, I am supposedly to have a soil that is mildly acidic but also alkaline. Isn't this a contradiction? and if not, how can I achieve this? What are basic additives and/or soil bases that produce acid and alkaline properties, respectively?

Answer 1

To produce a more acidic soil, we would increase the proportion of peat in the medium mix. For a more alkaline medium, we would add a shot of lime from the local grain growers' co-op. Note that messing with either of these also changes the water retention qualities of the soil. Schefflera do not like to sit in soggy soil (which a high peat content can promote), so be a bit careful.
That said, all schefflera do fine in a good quality balanced potting medium like what you can buy at your local garden center. They do not require terribly acid soil. And yes, acidic soil and alkaline soils are contradictory. There's no way to have both in one mix.

Answer 2

Scheffies thrive in regular potting soil. They enjoy (miracle grow) fertilizer every 3-4 weeks. I think the acid/alkaline thing goes something like this: coffee grounds or tea bags added = acid. Lime = alkali.

They love living outdoors durning the spring and summer here in SC.

I see the delima of your contradiction. Good luck.

Answer 3

It certainly sounds like a contradiction.
Acid soils are organic based, (humus, manure, peat) Alkaline soils usually have a high calcium carbonate base, (crushed limestone, chalk or fishmeal).
The conditions they prefer is probably dependent on the variety;
http://en.wikipedia.org/wiki/Schefflera

Answer 4

Add limestone to raise the PH. Granulated is slower acting, probably not what you want for house plants; pelletized dissolves quickly, and hydrated is the most efficient. Get a good ph testing meter.

You can use aluminum sulphate to lower PH with reasonable precision.

Answer 5

http://hgic.clemson.edu/factsheets/HGIC1511.htm
Scroll down to "Culture", and read "Repot", Then click on "Potting Soil".