No, coffee grounds do not keep hydrangeas blue on their own.
Specifically, the blue blooms on the hydrangea are the result of the plant being able to take aluminum from the soil into the roots. Aluminum has to be in soluble form for plant root intake. A soil that is too dry impedes adequate aluminum intake and therefore proper blue blossoming. Coffee grounds work to retain moisture in soil.
Yes, coffee grounds keep rabbits out of gardens, according to anecdotal, not scientifically researched, gardening. The leptorids in question prefer to avoid harsh textures and strong smells. Fresh coffee grounds tend to reinforce acidic power of hydrogen (pH) while unwashed grounds will lower soil pH and used grounds will function neutrally.
Coffee filters keep the coffee grounds from falling into the finished coffee during brewing. Coffee grounds are necessary for percolating, but are not good to drink because they have an unpleasant texture. Coffee filters are very effective for this purpose.
No, it will make them pink; baking soda is alkaline, so the pH will increase. If you want to make them blue, you should put rusty nails in the soil. In an acidic soil (pH near 6), you'll get blue flowers.
In the future take coffee grounds out of the machine right after every use and keep top of machine open to help machine dry thoroughly. Clean the machine at least once a week.
It is very easy to grow hydrangeas in Queensland. They virtually grow wherever they are planted. Out west, they will need more water, and it is still important to keep them watered well in coastal areas during dry seasons. A fact sheet on growing hydrangeas in Australian conditions can be found at the related link below.
Yes, African violets like acid soil, some people mix coffee grounds in around the soil to keep it acidic.
One way to keep cats out of your garden is the following: Every time you make a pot of coffee, set aside the used coffee grounds until they are dried out (you can continuously use a plastic container specifically for thisa purpose). One the used coffee grounds are dried out, take them out to your garden and spread/sprinkle them in and around the area where you don't want cats going. The extra benefit of this is that the used coffee grounds have certain nitrates in them that plants love and therefore they are a good fertilizer as well.
keep cats off your porch with coffee grounds and/or orange rinds and/or something shiny == == ----
pour the water from the carefee into yhe rejevior of the coffee maker and place the carefee back into position
The Westbend 33600 Coffee Maker will keep all stored coffee hot, and at a pleasant temperature.
Hydrangeas grow different colored flowers depending on the pH of the soil.
Some of the best ways to keep bugs away without using pesticides in the garden, are to use egg shells and organic products such as used coffee grounds. The acidic nature will help ward off bugs.