What's good or bad for the rose bed depends on what is already in the soil, so it's always worthwhile getting a soil test through your county extension service.

Gypsum is highly beneficial on alkaline soils with a high sodium content (sodic soils). It causes harmful sodium to leach out and be replaced by calcium, while improving soil structure. (Calcium sticks clay particles together in crumbs.) On alkaline soils with a high calcium content (calcic soils), it is useless. If the soil is very acid (below 5.5), you should apply limestone rather than gypsum to raise the pH while supplying calcium. If clay has a desirable pH of 6.0-6.8, you might get some benefit from gypsum or not, depending on how much calcium is already in there. I know you will get textural improvement by digging in 2-3" of manure.

I'm not aware of any likely problems from applying gypsum. It is moderately soluble and will probably leach out after a number of years. It would act faster on soil texture than limestone. Throwing some in the bottom of the hole in hopes of improving drainage is probably harmless, maybe helpful.

Please check on the pdf doc. that tells you in detail how gypsum can help or harm your gardening:

puyallup.wsu.edu/~linda%20chalker-scott/...files/Myths/Gypsum.pdfâÂÂ

Here is a working link to what kousa posted.

Here is a link that might be useful: Chalker-Scott on gypsum

Michael & Kousa,

Already found it and pasted what I thought to be the most pertinent to my new garden:

"Gypsum can have negative effects on mycorrhizal inoculation of roots, which may account for several reports of negative effects of gypsum on tree seedling establishment and survival;"

The Dr. Earth Rose soil contains mycorrhizal which is the
primary reason I purchased it. I believe that 'm' is very
beneficial to new root health.

Thank you both so much for your answers....Since I already purchased the gypsum, but haven't received it, I am happy to know prior to using it that It's a 'no,no'.

Your answers also answer one of my earlier questions about applying and mixing in another layer of compost.

I have ready a lot recently about VERY heavy and non-draining clay soil. I have also decided that mine isn't quite as bad as I thought.

Thanks again....Off to pick up my new babies from Regan's in Fremont. They will be planted (without gypsum) next weekend.

Thanks so much again,

andrea