Huge problem with blossom end rot, looking for advice

I have several questions and would appreciate any feedback.  
First off, I had a huge problem last season with blossom end rot in my tomatoes, squashes and melons.  I tested the soil and the pH was 7.0.  I always add crushed egg shells to the compost and fertilize with a combo of bone meal and blood.  There were some pretty severe temp fluctuations, but that will hopefully be remedied this year with a shade cloth and more ventilation.  I am very careful with watering, but I am planning on adding drip irrigation and  a thicker layer of mulch.  I am wondering what the general opinion is regarding mulch materials.  I am not a huge fan of straw due to the massive sprouting that has happened the last few times I've used it.  If I use wood chips/wood shavings will it disrupt the nitrogen levels?  I am converting to the no dig method, and plan on adding more fungi and worms to soil as well.  Does anyone have any ideas on what else I should do to prevent the blossom end rot?

 I am in Central Oregon and our soil is pumice.  It has improved over the last few years due to massive amounts of compost, chicken/pig/rabbit/horse manure, straw/hay and sheet mulching.  There was not a worm to be found when we moved here, but I have added them and they are starting to stick around (we had to get rid of a lot of ants first!!).  Thanks so much!!!

Blossom end rot (BER) is a calcium deficiency problem. It can be due to lack of available Ca in the soil, but can also be due to uneven watering which can cause the roots to not be able to access the Ca when needed.

You probably need to figure out if it is your soil being low in Ca, or uneven moisture levels causing issues with the availability of Ca in the plants, or both. With a pH of 7.0 you probably don't want to be adding more lime, but gypsum is a source of Ca which will not raise pH. You can also supply Ca in a foliar spray to the growing plants, which will help control BER when it appears. And some varieties are more susceptible to BER (roma/paste type tomatoes for example). And high levels of N in the soil can also hurt Ca availability.

Might be a good idea to get a soil test to see if your soil is low in Ca, as well as the other nutrients.

Thanks for the response.  Getting a soil analysis is really expensive here, so I need to research if you can have too much calcium in the soil.  If it doesn't cause any problems I may just add some gypsum, correct watering problems and hope the problem is resolved.  I still need to figure out the best mulching material.  Thanks again!

Kathleen Driscoll wrote: Getting a soil analysis is really expensive here

Have you checked this lab?  Their fees don't seem that bad.  Looks like $12.00 to test for Calcium.   http://www.al-labs-west.com/fee-schedule.php?section=Soil%20Analysis

My approach to blossom end rot, is to grow my own varieties of tomatoes, and to never save seeds from any  plant that produces even a single fruit with blossom end rot. It's easy to keep track of, because the day I see blossom-end-rot on a tomato plant, is the day that it gets yanked up by the roots. What that means in practice,  is that blossom end rot doesn't exist in my garden, except on new varieties that I am trailing for the first time. I think of blossom-end-rot as a genetic defect,  not as a calcium/water problem.

Thanks for the info.  I have not saved any seeds from the affected plants.  It was such a widespread problem last year that I am very concerned about what's going to happen this year.  I usually don't have garden anxiety, but I do now .LOL.  I have ordered some different varieties, and taken such additional precautions so all I can do is hope for the best.  Thanks again.

Kathleen, I'd get a soil test if you possibly can. While one might be able to select for varieties/plants better able to deal with Ca in your soil, the problem is due to Ca deficiency whatever the reason (missing in the soil, uneven moisture, low plant adaptability in getting Ca, etc). And sounds like you not only saw the problem in tomatoes but other vegies as well. For it to be so widespread, I'd guess that it is likely more than just a few plants that can't find their Ca, but that's the sort of thing a test will tell you. If you can't do a test, putting down some gypsum is fairly cheap ($10 per 50# bag here), and making some Ca spray to use on the foliage if the problem appears is relatively cheap too.

To answer one of your questions, no, adding wood chip mulch will not tie up N in your soil as long as you leave it on the surface and don't till it into the soil.  The only point of contact between your soil and the wood chips will be the thin band of soil right at the surface.

In fact, you'll see nitrogen levels rise because of all the worm activity that will follow from laying down a layer of wood chips.  If you wish, pile the chips up for a few months and let them break down a bit before spreading them.  When you are ready to plant, simply rake them back and find the soil below.  They will break down quickly as microbial levels within the soil rise.

Best of luck with the blossom end rot.

Thank you for the response.  I think I will use wood chips, I don't want to deal with sprouting straw again.