Won't the grasses hide the pond, too?

No. It’s hard for the photo to convey that the pond is higher than the swale or back yard.

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I'd plant up the swale like a rain garden.

The swale is not our property - our backyard goes up to it. I should have explained that😉.

So the entire thing is likely to floor on occassion.

We really can't give specific recommendations without a location. Around here, I'd lean more towards red twig dogwoods and yellow twig willows than grasses. YMMV.

Location is Columbus Ohio😉. Southern exposure.

Panicums are tall native grasses that can handle both wet and drought. Many handsome cultivars.

Is the pond a natural pond fed by an underground or open stream or is it manmade? Is it used for recreation? If natural, your best choice is native plants and no pesticides or herbicides. Many ornamental grasses are invasive. I suggest checking with a local native plant nursery. They are always happy to advise and help with planning. I found one near Columbus, but I am sure there are others. Link below:

Scioto Gardens

ps. For the color scheme you want, perennials would be able to give you that. Most grasses, especially native ones, will not. Lots for good native pernnial choices for your area though that would be perfect.

Panicums.

If location appropriate the dogwood suggestion is good. They would give the best colour in the winter when grasses would either be brown or cut down. Better still, combine both.

Thank you! We are planting Lavender Crape Myrtle on each corner - similar to dogwood and Ohio native tree.

Will incorporate some evergreen types to add Winter color - thank you for the ideas!!! I appreciate it!!

Just to be clear the dogwood colour comes from the bare winter stems. They are not evergreen. Not sure I understand the comment about the Crape myrtles. They are not similar to the suggested dogwoods, which are shrubs not trees, and they are definitely not Ohio natives. If that's what you meant.

Dogwoods are trees - not sure what you're referring to as a bush. My question was which grasses to plant. I've gotten answers that are almost everything but grasses. Thanks anyway!

Amy, I suggest you do a little research on Dogwoods. You'll see there is a large variety of species and cultivars. The ones mad_gallica is referring to are definitely shrubs and are grown specifically for their brightly coloured winter stems, enhanced by periodic coppicing. They are not trees and they do not produce the showy flowers you are probably thinking of. https://www.monrovia.com/be-inspired/dogwoods-winter-color-1120.html

While you are at it, do some research on crape myrtles too. If they survive at all in Ohio, they will act as dieback perennials, not trees.

Also, any color provided by ornamental grasses is very transitory and occurs late in the season. Most are not invasive (at least in Ohio), intolerant of wet soils and rarely will grow tall enough to provide much screening, which will also be transitory due to their growth cycle.

My question was which grasses to plant. I've gotten answers that are almost everything but grasses.

Perhaps that is because the request for grasses with purple, orange, and yellow whimsical colors is hard to answer. For orange, there are some carex grasses (Sedge) that are wonderfully orange-check out Prairie Fire Orange. Purple is tough because most are really not a pure purple even if the word purple is in their name. Yellow will most likely have to be a yellow green shade actually. Some of those that might suit you probably have 'gold' in their name.

Try an internet search for each color to see if anything would work for you. Also, do be cognizant of invasive grasses which can wreak havoc with the environment. Again, check out local nurseries. They are always happy to help.

My comment about color is those are the flower colors that will go in front. Not the grasses.

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Amy, good to know. You didn't mention anything other than grasses in your OP, so that may have thrown people off.

What's wrong with Panicums?

The problem with using ornamental grasses to "hide" the swale is that they will only be doing so for a few months of the year. They will need to be cut back to ground level annually. As will adding whatever color you like from herbaceous perennials. You are looking at really only summer to early fall for any kind of visual appeal and/or any screening or 'hiding'.

Adding the shrubby dogwoods makes a great deal of sense and will extend the season of interest significantly.

What do you mean by whimsical?

As your plant knowledge seems to be a bit limited, it might serve you best to hire a qualified local landscape designer to help you plan out this project and select the correct plants for your needs and this situation.

TY that’s helpful! I’ll take a look at the dogwoods!

The link I gave above has information about Dogwoods. Here it is again. https://www.monrovia.com/be-inspired/dogwoods-winter-color-1120.html