Nice to see a swing in a walk-away destination - quiet spot. Idk what could be done if that's a water-filled area with rain. Maybe shrubs that need water. River birches like water.

I'd start with trees for a sense of privacy.

I can't comment now as I must go out, but can you give us an idea of your budget? Hardscaping can really transform a garden but it can be expensive.

Also, is this a garden for kids to use? Do you want to entertain there, perhaps?

Be back later, I hope.

Tell us where you are, what direction the house is in comparison to the back yard, and how you want to use the yard. Garden shed, kids' play structure, soccer practice, cut flowers, privacy, outdoor living, BBQ, etc. etc. Do you need shade for your patio or a larger seating area or a vegetable garden? Function has to come before you can make plans.

What is the green hatch - septic cleanout or utilities? Is water typically slow to drain? In general what is your soil like? Do you own all the fences or not the one on the left of the photo?

All important questions! But just on the aesthetics, I was thinking of something like this?

thank you all for wanting to help me, I am attaching couple of pics from different angles.

to answer some of the questions:
I would like to keep a barbecue area and the swing.
I am not sure about my budget, as I don't know what can I get.
I am thinking to buy plants, but not sure how many or which ones.
I want to give it some dimensions, as it feels very flat.

2x2 Decktiles are affordable and would be a nice addition laid right down on top of the concrete pad. Each tile weighs about 25lbs so if you can lift 25 lbs you can do the install yourself.

Unless you bring in a lot of soil to make mounds or berms it will remain flat! But you can add dimension by having layered planting beds, including plants with a variety of heights - the plants will provide the dimension :-)

Until you have a plan worked out - where to locate what - we can't help with what plants or the number. And where you are located geographically is also important as to plant selection.

Unless you engage a design professional, my suggestion would be to use graph paper to work out a design that you are happy with. Layered beds need depth so be generous with your sizing - 6' at a minimum but larger is better. Include placement for a couple of smaller trees - Japanese maple, redbud, crabapple or dogwood - they will provide some dimension due to height. Then fill in with smaller, fuller shrubs and perennials.

I would also encourage you to increase the size of your patio - builder's patio pads are ridiculously undersized! You can use square concrete pavers to extend the patio to a more generous size and relatively expensively. And it is not a difficult DIY project.

thank you for the suggestions, I am located in WA, lots of rain here. and the recommendations of trees and plants is what I was looking to give some dimension.

Check out Great Plant Picks - this is a website developed specifically for PNW gardeners with lists of plants for various growing conditions that thrive in our climate and are widely available at area nurseries and garden centers. Sizes are provided under each specific plant listing so you can determine proper placement.

wow, that looks awesome, thank you

Jan I suggest keeping the barbecue area somewhat close to the house, since that's where your table is and also where your kitchen is. Not too close so that the smoke gets into your house, but closer than by the swing. At my last house, I had a swing on the opposite end of my house, it was a "destination" for relaxing. I would start with landscaping that area, with shade trees and then sit on the swing (I'd bring it out more so you could plant behind it, like a "C" shape enclosing it). While sitting in the swing, imagine what would please you to view. My yard was much smaller than yours, but I had a little island with a fountain and some pretty trees and shrubs and flowers, a "pleasure garden" designed for viewing. Lots of white plants that looked good at night, because for me, that was when I had the most time to be out in the yard, and not so hot as during the day in the summer. But I didn't have a mosquito problem at my last house. YMMV for the time of day you will spend out there. If you don't want a fountain, maybe some type of planter or garden sculpture.

As for your budget, I would start with the trees. They are the biggest cost and take the most time to grow, and will make the most impact. HOWEVER, you don't have to spend a lot and buy big trees. Little trees grow fast and make up for their small size faster than it takes big trees to adjust to a new spot. You should be able to find trees for well under $100.00 and many under $50.00.

Here's a picture of my pleasure garden with its little fountain. There was a fireglow Japanese maple in the middle of it but it died, :( You could put something similar off your patio, but with bigger plants since your patio is farther away. But you'll have to deal with that water issue somehow! There are plants that can work in wet spots but it look like you have an overall drainage issue in your backyard . . .

this is great! thank you so much for taking the time of sharing so many great tips, your garden looks awesome, please share more pictures if you have :) again thanks a lot