I put new mulch in flowerbeds last summer, and now there are mushrooms sprouting up all over. Very frustrating, can someone please help me?
You can treat the mulch with a fungicide to reduce the mushrooms. Also, try watering in the morning, as opposed to the evening so that the mulch has a chance to dry out some over the day so it is not wet at night, which is when the mushrooms are most likely to grow.
When I turned my mulch/soil in my garden beds, there were small white bulbs or balls and the mulch has a white dust all over it. What is this? Mold? How do I prevent it?
It is mushrooms, essentially. This article will help:
All of the plants in all the beds did not grow as they did in past years. Someone pointed out that walnut stunts the growth. Would this be the case of the dark black mulch? I used dark black mulch last year and I had a very poor showing of flowers. The retailer claimed there were NO walnuts in the mulch.
It would not have contained black walnut. But, if you use mulch every year, the soil may be depleted of nitrogen, which would stunt plant growth. You should have the soil tested to see if this has happened.
Another possibility is that the mulch was dyed, which has its own issues. This article has more on that:
I have just started noticing a white looking, powdery-like fungus in the mulch around the plants I recently transplanted. It's only spreading on the mulch and has not gotten on the plant leaves yet. Can you tell me what it is and how to get rid of it?
This is powdery mildew. Powdery mildew is caused by fungus. For more information, here is an article or two that you may find helpful: https://www.gardeningknowhow.com/problems/get-the-cure-for-powdery-mildew.htm
It can also be treated effectively with neem oil. Here is more information: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm
Is there any risk of mold forming when leaves are raked and brought around the base of a tree? My concern in this wet Oregon winter climate is that this is a good environment for mold to reproduce and kill grass.
Yes, any time you leave dead material out, there is the potential for mold or other problems (such as pests, disease or fungus) to develop, especially in wet environments.
I would recommend that if you are going to leave the leaves piled up around the tree, that you chop them up with a lawn mower. This will increase how quickly they decompose and reduce the amount of time they potentially have to develop a problem.
I have a large yard and usually put 8 yards of mulch on all the beds every year. I have lived in this house for about 6 years and I have been wondering if I am doing the right thing. I have to first pull all the weeds before I put the mulch on and this is a real pain. I have been thinking of a different approach. I was wondering if I could rake all the old mulch off the beds and then use some type of cultivator to get rid of the weeds and loosen up the soil. Then put the old mulch back on and replace any areas that need it with new mulch. I probably wouldn't need near as much mulch. What do you think?
You can also try using a weed barrier below the new mulch. Thick layers of newspaper, cardboard or landscaping cloth will work. You can lay the new mulch over the old without having to weed. The weed barrier will kill the weeds (by blocking the sunlight) and keep them from growing up through the mulch.
I found hundreds of tiny black eggs - maybe even thousands - in some mulch near my house. What could they be?
Hard to tell from this information, they could be many different things. Your best bet is to take some to your nearest extension service, or contact an entomologist at a local university; someone there may be able to identify the eggs.