I'm not at all sure that this is going to be enough to fill the site.

The site where we are planting is an incredibly long and thin median strip in a parking lot (it's about 144' long, 4' wide). Here's a view from Google Maps:

We are also planting up the two "lobes" at either end.

I would be incredibly grateful for any help at all, but let me give you my top questions:

1. JUNEGRASS (koeleria pyramidata) -- how "substantial" a grass is this? The pictures I've seen online seem to show a shortish crown and then fairly spindly grass coming up at the height of the season. And how wide does it spread? One idea is to fill the 4x144 median with the junegrass. Would a single line of this work, or would that be too thin-looking? Would a single plant fill a 4' wide spot? Or should we stagger two rows? And what kind of spacing would you recommend? We have 76 plugs of this, but could get more if necessary.

2. WILDFLOWERS. We are getting 8-10 each of the following: aster laevis, baptista australis, coreopsis lanceolata, coreopsis tripteris, eryngium yuccifolium, pycnanthemum virginianum, rudbeckia fulgida sullivantii, silphium laciniatu, solidago juncea, solidago rigida, zizia aurea. My idea (as I said they are not giving me a whole lot of time to think this through!) is simply to plant the tallest plants in the center of each "lobe," around the lightpole that is already there, and then work out towards the margins with the shorter plants. The lobes are hard to measure but about 19'x11'.

Question #1: will 88-100 plants fill even ONE of these lobes?
Question #2: are these wildflowers going to look OK by themselves, or would you recommend mixing tall grasses in to anchor the bed and give us something to look at before the wildflowers bloom?
Question #3: do you see anything in this list that will be prickly, poisonous, or rash-producing for kids?
Question #4: these are all summer-blooming plants, right? And we are a school that takes the summers off. So can anyone tell me what this particular donor was thinking???????
Question #5: how awful is this bed going to look out of season/how much maintenance (deadheading, cutting back, etc.) would you say it will need?

Sorry to sound frustrated. I am a bit overwhelmed by this prospect. Have been given a lot of responsibility and very little control. I actually really like the idea of a prairie/wildflower garden and have one of my own at home but I do get to see it and tend it all summer...

Oh, one more thing. The school also just cut own two enormous fir trees and the person in charge of this project wants me to use the shredded up branches and needles to mulch this wildflower bed. Are pine branches and needles a good mulch for wildflowers? I think I know the answer to this but would be glad for some expert opinions.

PS I get three volunteers for three hours on Saturday morning to dig up the existing weeds and install and mulch this beauty. Waah!

It sounds like quite a project. Here is how I would handle it:
- Go for mass plantings, except for a the silphium and baptisia. They get big and like their space. If the strip is 150' long, plant a patch of a species every 15 feet. Plant them 1' on center apart from eachother. In between each of these groupings you could alternate baptisia and silphium. I would save at least one silphium for the middle of each lobe at the ends though..
- After that, use the junegrass for an effect. Space them evenly between each grouping or simply put half in one lobe and half in the other.
- I wouldn't just do a sporadic planting. Grouping allows for easy care and watering. Assume this may not be the last time plants are donated. What if there are future plants? Where will they go?

I hope that helps a little. It seems like a project that is being rushed a little bit too quickly. You would think that the nursery would understand how much time is needed to make something like this actually work well. If there are weeds and grasses in the area you will have problems in the future. In the event that you ever get a project like this handed to you again, glyphosate the area right away. A few days after that you can plant right into the sod without risk of hurting your plants. Also, I wouldn't worry about mulch if the area is weed-free. Prairie plants are built for dry weather and mulch doesn't help a plant with roots that go down several feet that much really. If you didn't use glyphosate though, mulching around the plants to control weeds and establish the plants might help a little.

As for care of the plants after the growing season, just take a strim trimmer and whack them to about 6" above the ground unless you plan to collect the seed.