@Plumeria Girl (Florida ,9b) had this done. I know she's very busy now, but maybe she'll have a suggestion.

Katthyc, your numbers are very high. How reputable is this company ? All I know if something is high, do not add anything.

I was reading below the tables about prior to planting. It recommends you to spread below requirements Gypsum 10, Elemental Sulfur 20 and Nitrogen 20. Nothing else.

Seems you salt is very high and having drainage problems. Your Micronutrients are very high too.

I would just follow what they recommend or call them up. I wish I can be more help.

Good luck, my rosy friend !

Join the website “around the yard”. They will read soil tests and make recommendations for you. let them know this is for flower beds, not the lawn. They guy used to do it here on the Lawn forum has moved over there. Really knowledgeable, helped me a ton!

@kathyc_z10_socal if it helps, a friend in Florida who works as a County Extension Agent posted this list of soil test sites state by state. Perhaps you might also find information from some of them. https://gardeningproductsreview.com/state-by-state-list-soil-testing-labs-cooperative-extension-offices/ 

You should not worry about the amount of water you are applying even though you have high ph water. The added sulfur will lower your ph and counteract the effect of the ph of your water.

Urea is ok, just divide the total amount needed into smaller applications. I use elemental sulfur, not a named product, for temporary lowering of ph.

If the depth of your soil sample included both amended and native soil, your soil may be in better shape than the soil test indicated.

You said that these beds were not thriving. It might be better to analyze the roses' foliage and growth. Do the leaves show minor deficiencies? Are they undersized or misshaped. If you post photos of the plants and foliage, there are experts on this forum that can tell you what you need to do.

Salts build up in California soils in years of low rainfall, which we certainly have had. In particular I skip my spring application of composted manure unless we've had a good winter rainfall (definitely skipping it this year).

Many California soils are low in nitrogen and need yearly applications.

I agree that consulting the lab that did the testing might be a good idea. And tell them what you are growing. Many people are growing lawns or vegetables. The requirements might be a bit different.

I know some have questioned the numbers you got. I, OTOH, believe them. My water runs around 8.5

I also don't want to be discouraging, but I have found over many years that because my WATER is so very alkaline, my soil will constantly revert, no matter WHAT I put in there. But you can use soil sulfur. I've had Ironite recommended, but of course, it is very slow acting.

I have also found over the years that no rose with a high % of Multiflora in its background is going to be very happy in my conditions. I can grow Poly-Teas, for instance, but regular Polyanthas are going to suffer. Purple roses, for the most part, don't do well, because they go back to Multiflora.

I have seen White . . . WHITE leaves on 'Reine des Violettes' and 'Excellenz von Schubert'. When the problem is that severe, mending it becomes a full-time job. Now, I just don't plant roses here that won't handle my conditions.

Do you see chlorosis on your leaves? Davis has some good information about soil levels needed for roses. They also mention electrical conductivity above table 1. http://ipm.ucanr.edu/PMG/PESTNOTES/pn7465.html

Also more explanation about interpretation of soil tests. I found this after looking for explanation for my soil test results. http://iv.ucdavis.edu/files/24409.pdf

Plus a nice summary of the soil types in California.

https://www.cpuc.ca.gov/Environment/info/aspen/atp2-3/EIR/Section%20C/C5-Geology-Soils.pdf

This discussion is about P and K deficiency, which you don’t have, but I found it helpful in deciphering the language used in the test results. http://calag.ucanr.edu/Archive/?article=ca.2016a0007

Stephanie: I looked through your links, fantastic info. Thank you. The first link was where I got rose tissue analysis (done by U of CA at Davis) back in 2014. Rose-tissue analysis: more nitrogen than potassium, 1/2 calcium, 1/10 phosphorus and 1/10 magnesium.

Kathyc_z10: See below link for info. on alkaline-soil & fertilizer. Below link shows my discussion with BirdsLoveRoses .. she has pH 9 to 10 soil with high salt. She has pH 9 tap-water like I do. If you have any questions, I'm ready to answer here too. My soil test back in 2011 was pH 7.7 with exceedingly high magnesium & low manganese & low calcium. I did gypsum like they recommended, but if I have to do it all over again, I would focus on organic matter (alfalfa and cracked corn) to UP the nitrogen & moisture, rather than gypsum which DRIED OUT MY CLAY (I have rock hard alkaline clay).

https://www.houzz.com/discussions/6111804/soil-ph-soil-type-moisture-fertilizer-for-certain-roses#26816464

Below is a thread which I wrote on gypsum is best FOR THE BOTTOM of planting hole only. I also included a map of different soils across USA:

https://www.houzz.com/discussions/5971487/calling-strawchicago-re-clay-alkaline-soil-amendments-fertilizers

I think adding organic amendments to the soil is crucial for soil health, but I agree with Jeri - it's a constant battle to get the soil pH down near neutral and keep it there while always adding alkaline tap water.

You could try adding Alfalfa Pellets to the soil. Strawchicago says they add acid as they break down. Also a source of Nitrogen for you. I haven't tried it yet, but it's on my list...

Stephanie - thanks for all the links