Since there is no scale indicated, it is hard to be very precise about spacing. But it doesn't look too crowded to me. Full - but not crowded :-))

Unless a single specimen - like the crabapple - typically plants on a plan are shown in clusters with the individual plants touching. And they are generally drawn to a scale that reflects them in their potential mature size or very close to it. At the initial planting time, it will generally provide a much more sparse appearance, only filling in as the plants mature and eventually 'touch'.

Low maintenance depends much more on the particular plants selected and very little to do with their proximity to each other. Just based on the plant selection outlined, I would not consider this a very low maintenance planting plan.......more in the medium range. Perennials are towards the top of the maintenance scale (only exceeded by annuals and edibles). Deciduous shrubs are generally lower maintenance, evergreen shrubs and conifers are lower still. For example, I would consider a very low maintenance planting plan to be one that focuses on broadleaved evergreen shrubs that do not require any regular pruning to keep size in check, dwarf conifers, most ornamental grasses and well-behaved evergreen ground covers. There are some perennials that do not require as much maintenance as many others and I might toss in a couple of those for more seasonal interest as the rest of most really low maintenance plantings tend to be somewhat boring :-))

Thanks for feedback! I didn't realize the scale was cut off. It 1/2 inch to 1 foot.

But since we're looking at a picture of the piece of paper, 1/2" = 1' does not translate.

Correct me if I'm wrong (it was a bit hard to figure since things are labeled a little weirdly) but it looks like a tree with a collection of shrubs and perennials below ...?? If that's correct, I view the shrubs in that situation as high maintenance when they are used, in effect, as a "groundcover." It's too much trimming. God help you if you trim them like separates as that is really time consuming. Other than that, it's too busy for my taste.

Totally understand that scale doesn’t help for the photo... which is why I tried to give the dimensions and the size of plants, but I appologize that it’s confusing. The names were done by the designer, and I pulled the sizes after looking up the names on the internet so she might have different varieties in mind.

I asked for professional help as I needed suggestions for how to work with the sloped bed, so do need ground covering. I just don’t think I was expecting so many bushes and concerned it will be overgrown in a year or two.

Two other concerns is that it feels kind of symmetrical against the garage wall and I’m wondering how that will look with the buckthorn being at two different elevations. And the plants in the corner won’t be easy to get to..or even visible once everything matures.

I’m torn between trusting the professional planner on this or voicing my untrained landscaping gut instinct.

Thank you! I guess it just scared me a bit to picture this area with 9 shrubs that are over 4 foot high, a tree and 20 plus plants that are between a foot to 3 ft. tall. I understand we need more plants to keep from eroding, and as I said I’m not very familiar with landscaping.

I think there is space for shrubs at the window wall, a tree, and one type groundcover. Maybe a patch of perennial at the other wall. And if you want to add something else, do it after you see the simplified version and think the need is still there. I guess I'm saying trust your "untrained gut instinct."

Plant the tree, and whichever 3 of the perennials you like. Then fill in later if it seems too bare.

So is there a good rule of thumb for planting to keep the erosion to a minimal? That’s what made me start this project in the first place.

The rule of thumb is PROPER GRADING. Surface water should pitch away from ALL walls, including the back of the retaining wall. If it pitches toward the wall, water will begin eroding earth from behind it. For the plants, it is primarily groundcover that will protect against erosion. Mulch works temporarily if the grade is not too severe, but groundcover plants work permanently and tolerate much greater volumes of water while still protecting. Various perennials can act as groundcover, with the results depending on their particular characteristics.

So given our slope and dimensions... are there certain plants or a certain number of plants that we should put in? Wondering if this is why the above plan is so heavy?

Your slope is not that difficult. How close to one another you plant a groundcover plant depends on what it is. They spread at different rates. Liriope muscari is an enlarging clump so relatively slow spread. Liriope spicata (not suggesting it) spreads by underground roots at a rapid rate. (It's also much more difficult to limit unless one installs a root barrier.) Commonly, it's 1' to 2' spacing for most gallon size plants, which allows for solid coverage in a reasonable time.

Thank you yardvark!

One year later...

we scaled way back on suggested number of plants and made substitutions on others because of availability. I may fill in a bit more but overall fairly happy with the space. I truly don’t think we could have fit the number of plants and bushes originally planned by the landscaper designer.

i think once the bushes mature a bit and we add a few more ground cover plants it should look good. Always open to additional suggestions too!