Hi Maid. ES's will not make any difference ridding mildew. Your ivy needs air circulation, so open the window, weather permitting..as long as it's not too cold, especially if plants are sitting before the window.
Also, let soil dry before watering.
Humidity is necessary for tropicals but high humidity and no circulating air poses problems. Rot/mold/insects.

Epsom Salt, once a month, keeps leaves nice and green. I wouldn't use ES's with every watering. 1-2 TBLS, per gallon of water, once a month is adequate.

If your soil is staying wet, you either need to decrease watering or change soil. Good luck, Toni

Adding Epsom salts to your plant w/o adding calcium (Ca)can create a deficiency of Ca (Search calcium magnesium antagonistic deficiency). The effect of adding 1-2 tbsp of Epsom salts to a gallon of water and then applying it to your plants is virtually the same as adding 1-2 tbsps of fertilizer to the water and applying it. This will raise the TDS (total dissolved solids) and EC (electrical conductivity) levels of the soil solution to extremely high levels, and can cause plasmolysis (fertilizer burn) - especially if the application is close to your regular fertilizing time, because you have the Epsom salts + your fertilizer salts + residual salts in the soil. 1-2 tbsp/gallon doses also virtually assure a Ca deficiency unless you add Ca at the same time.

You should be sure you have a Mg deficiency before you use MgSO4 (Epsom salts), or using it is always counter-productive.

When you DO have a Mg deficiency, 1/8 - 1/4 teaspoon per gallon of water along with your regular fertilizer (that does not contain Mg) is enough to alleviate the deficiency.

Al

Hi.....I know this is a different condition but will the epson salt spray also work to get rid of mold on the top of the soil....every year when I bring my plants in and the weather gets colder, the top of the soil grows mold...
why? is it the cold, I try to keep my plants alittle more dry in the fall-winter-spring...I just don't know why I get the mold...any help would be very helpful and appreciated.....thank you....linda

Linda - are you sure it's 'mold' and not dissolved solids (like the build-up in a tea kettle) accumulating as water evaporates from the soil surface & leaves the dissolved solids behind? That's a very common occurrence in the winter, & the residue is often mistaken for mold.

Al

HI....yes its mold...I only get it this time of the year...
when the house is cooler.......any ideas how to get rid of it....linda

emerald1951, Do you have steam heating system? I have had that problem with my orchids in the winter and I have steam heat and the orchid. I put decorative rocks on top of the orchid soil which is a just bark and a little bit of sphagnum moss .

I think it is because of the steam heat I do not water my plants much at all so they are usually very dry but the orchid never dries out couple that with my steam heat I get the mold problem.

Linda (and Marquest) - steam & hot water heat systems are closed. IOW, the water in the system never makes it into the air in your home; so compared to other heating systems that would get their make-up air in similar fashion to the way your system gets it, there would be very little difference in humidity levels - especially not enough that it would promote mold growth. Old systems often get their make-up air from inside the home, newer heating systems utilize outside make-up air. The older systems are drier because they pull cold dry air in from the outside to 'make-up' for the air lost through the chimney stack.

Linda - If it is mold, anything antifungal should help combat it. You could try a sprinkle of cinnamon, watering with weak chamomile tea, a light sprinkle of flowers of sulfur .... The first thing that comes to mind though is to be sure you're not over-watering. Check the soil down deep in the containers with a wooden skewer or chopstick. If it comes out damp or dirty, withhold water until it comes out dry.

Al