Maroon and blue are two of the rarest and most challenging colors to achieve in a garden setting. Especially if you are new to gardening and hoping for low maintenance. Hydrangea shrubs might provide blue, depending on your soil and sun exposure. Some cosmos varieties are maroon, but would require very different conditions than hydrangeas. Good luck.

Martha

Helictotrichon (a grass) provides a good blue and some Heuchera will give good maroon/purples. The grass is semi-evergreen and is not cut back in spring, just combed to get the dead strands out. Picea glauca globosa will give a good blue and is very beautiful.

I should add that the blues mentioned above are silvery blues.

I would like to keep a color scheme of green, maroon and blue to match the interior of the house.

==>>> never heard of this before .. why??? ...

is that south facing.. full sun??

is the space needed for snow removal .. i heard Chicago can get snow.. lol ...

what is the soil ... does it perk .. or drain ... is it rocky???

as a newb.. you have many things to address ... before you get to your color palette ... and 90 % of your success.. will be the prep work you do ... sorta like painting .. the actual painting is the least part of the work ... done right ...

ken

https://duckduckgo.com/?q=perk+test+garden&t=ffcm&ia=web

It seems erroneous to focus on a "color scheme" as if this is indoor decorating. What's happening here wouldn't have anything to do with the indoor scheme, as that cannot simultaneously be seen. Plants are not like paint, coming in any color. They have their own ideas. Better to focus on plants that like the conditions and perform well.

I agree with all the commentators who say that there are other factors to consider before you start thinking about colors. But once you have those things sorted out, here are some things that you can grow easily in Chicagoland that might provide some of the colors you are talking about: Yews for a bright green background, something white such as hydrangeas for contrast, mini-maroon is a Barberry I recently purchased, Iris come in all sorts of Blues and purples, Japanese maple Bloodgood, clematis jackmanni and etoile violette , centaurea Montana amethyst-in-snow, heucheras, purple pavement rugosa rose, ninebark diablo, catmint for blues, baptisia australis cultivars, sages, and no doubt many more.

No one asking a question like this has any hope except for a trial and error plan...which is a perfect path if you love gardening...do t mind

And dont mind putting in 10- 15 years to get to a garden with low maintenance ..survivors...i can attest to this from personal experience...at some point i had a nursery owner come out to layout $$$ worth of plants ...many of which didnt survive..and the rest took over...now i am happily pruning and thinning every year...just adding annuals in designated pots every summer.....

I found the best advice came from a really good garden maintenance contractor..who had been servicing gardens in my area for years...so...specific local help has been best for me..if you tour homes in your area and see yards that you love ...that are well maintained..they may be able to refer you

And maybe you can get a head start

Probably the easiest way to get maroon in your garden is to plant varieties that produce new,growth leaves that are maroon..or have leaves that change to maroon in the fall

From the picture it looks as if there’s a lot of work to be done on the soil. It looks like builders’ rubble at the moment. What are your plans for preparing the bed for planting? Choosing the plants is the most fun part but is also the least important.

Soil prep requirements will depend a little on the plants you choose.... and you didn't give info about your location to know what plants to recommend. You could go super low maintenance w/ xeriscape type plants (sedums, etc), or go with one-time plantings and minimal maintenance of things like barberry (maroon), creeping juniper (blue), etc., or slightly more maintenance w/ things like flowering perennials -- Siberian Iris, Campanulas, balloon flowers, etc, for blue... lilies, daylilies, dahlias, etc. would be good choices for maroon.