I do LOVE my red push pistache and I recommend them to many clients who want a beautiful shade tree. I do not think they are messy. Of course they go dormant so you need to be ok with no leaves in the winter. But each tree will act different depending on the temp where it is planted. I saw 2 today full of leaves! The pistache requires more water than our desert trees. The difference with the citrus is that you will want to do deep watering often in the summertime. You must be careful though and make a well around the trunk as you do not want the citrus trunk to ever get wet. You also want to fertilize the citrus and be sure to paint the trunks in the spring so they do not get burnt in the summer. I would stay away from the sissoos. Once you have them they will spread roots looking for water. If they reach grass you can bet on little babies popping up everywhere! I am an arborist and I cannot tell you how many we have removed in the past 5 years. Once removed none of the root system can have any water or sunlight or you will be sure to have babies everywhere. You definitely have room for the swan hill olive (fruitless variety) and I agree that they are super clean. They will send suckers up at the base all the time and you will want to cut these back. I really like the tipu tree also. It does get very large, has beautiful leaves and small yellow flowers. it will defoliate late winter and immediately send new leaves out again. Below is a baby and a close up of the leaves. I was really glad to see you have the trees spaced far apart. So many times trees are planted too close and end up competing for sun. I hate removing trees for this reason. Good luck!

Kitasei, the rocks are not actually landscaping filler. They are river rock mulch (as opposed to wood mulch) on a prepared shrubbery bed, separated from the lawn by metal edging. It's extremely common in the Denver metro area. When properly planted, these rock mulched beds are quite beautiful. It's just a different look from that seen on the east coast. ColoradoLime, you haven't mentioned your elevation. From what I am reading about the Abies koreana 'Horstmann's Silberlocke', it's mature width is 10-12', which might fit in a corner of your bed, however, it's not recommended above 6000 ft. If you're at a higher elevation, you might take a look at some of the Juniperus scopulorum cultivars. There are a number of very slender (3-4' wide) choices. You could even do a grouping of 3 in a corner with a groundcover at the base. Denver Botanic Garden has 2 beds with 3 surrounded by perennials. Stunning! One observation I would like to share - our daughter and her family are in a new home in Castle Rock, with an almost identical backyard setting as yours. ALL of their adjoining back-fence neighbors have planted trees within 2 feet of their own fences. As a result, our daughter isn't planting any. They are surrounded by trees! It appears that yours is also a new development. Just something to be aware of. Some things to consider (keeping in mind your elevation): Evergreen shrub - dwarf pinyon pine Evergreen tree - Picea glauca 'Pendula' (weeping white spruce) - 20-24' tall x 3-4' wide. This would be striking in the corner and definitely something your neighbors are not likely to plant. Evergreen tree - Juniperus scopulorum 'Woodward' Deciduous shrub - 'Mini Man' dwarf Machurian viburnum (good for small beds) Deciduous shrub - Spirea - there a many cultivars that remain small enough for your space and have lots of color during the summer and the fall. Perennials - too many choices to even list. Perennial heaven here! Have fun!

Hello Bob, Seems like you have a fun project on your hands. I can't speak much to the plant selection, as I am from all the way up in Canada, but I would recommend considering a rock garden for under the trees with some native shade tolerant plants and a focal element. The rockery would play nicely off of the existing concrete walkway, would be low maintenance for you and would fill in the space where it is hard for things to grown anyways. You could then utilized the pre-existing lawn for the children to play. If you are selling after that 5 years, this would add some curb appeal, would be nice for potential buyers and is easily altered if it is undesirable for them. However, this recommendation does not consider where the house is in relation to the yard and your desired 'flow' or usage for the space. Just food for thought. Cheers, Kyle

@greenfish1234 Thank you again for your input. I'm attaching a better picture of the back door area. Our door is currently a slider door - not sure if that will be switched in the future to a french door. How far past the door should the steps/landing go? The further we go, the further we cut into that dead space next to our family room wall (to the right of the door). Also, the deeper the total of depth of the steps/landing combined, the deeper the bed gets to the left of the steps/landing, unless we don't make that bed as deep as the steps/landing, but not sure if that will look right. I'm also attaching a pic of landing/steps I found on line. Not that I want curved steps or that material, but was wondering if I could turn that dead space into a raised planter on the landing. That way I can soften that area. If I did this though, not sure how far to bring out the planter - just to the last step, or to the edge of the back of the family room wall. In this pic, their dead space is probably 1/2 that of mine.