Boxwood is nice but very slow growing. Nandina (heavenly bamboo) works well and has good winter interest with berries and orangey new foliage. Nandina domestica is too tall for your requirements. N. domestica 'Compacta' may be too tall as well (about 4-5'). N. domestica 'Gulf Stream' is about 3-3.5' and very tidy. Do you really mean giant arborvitae? That is a monster - probably grows 3' per year, not 3' total. There are other evergreen shrubs that you might consider, but first determine if you want solid green or the more multi-colored foliage of the Nandina. There are dwarf Pittosporums, Rhaphiolepis umbellata 'Minor', and probably some others as well. I'd not hesitate to get the smaller plants. If they are planted in appropriate soil and given adequate irrigation until the rainy season (and you have to keep checking them if we have dry spells during the winter - you cannot let the root balls dry out and those root balls will be fairly small) they should do just fine and yes, will catch up within a relatively short time.

I would agree with borderbarb that there's probably not enough surface area to grow a lot of green manure but it's sounds like something I might try for the heck of it. Right now I have sunflowers and sweet peas growing out of compost covered hay bales. To what end I'm not entirely sure but they should look cool if they take off. I think if you want to grow your greens for your pile you're probably better off setting aside a section of your garden for it. Comfrey is supposed to be excellent for that but it is invasive. I have enough invasive plants growing already so I've kept away from comfrey. I'm growing some borage this year and that is supposedly a good green for the compost pile. Are you sure you can't scrounge up some greens? A quick search of Cleveland's craiglist showed a handful of people getting rid of hay which is usually a pretty good green in the compost pile. It helps having a pickup truck to get those sort of things.

I planted 50 leyland's 3 years ago. They were in the 5 gallon buckets, about a foot tall each. Now they are 12 to 14 feet tall. Not one has died, gotten cancer or been toppled. I live in Northwest Georgia. These trees have seen the most extreme weather our area has seen in years. Let me give some unsolicited advice, with all due respect. 1. Whether they are green giant or leyland or arbovitae of any kind: Make sure you know your soil, make sure you know your frost level, and make sure you PLANT AND WATER AND FERTILIZE them appropriately. If you don't have time to manage them, then don't plant them. 2. Plant them far away from structures you don't want them to grow into. i.e: fences, buildings, septic tanks, neighbors who hate their shade etc. 3. plant them double their pot width, ONLY to the top of the pot you bought them with and with 1/2 native soil and the other half conducive to your local weather and environment. Be prepared to tie them off with rope that have maybe some cut pieces of garden hose around the rope to keep them from choking and which will help keep them level in high wind times if you are in a high wind area. 4. Applying water and appropriate nutrients is huge, but easy. GG's and Leyland demand alot of water if on a slope with hard clay or dense soil. Down south if you are in red clay, then water them morning and night for the first month or two. If you are up north or in moist soil, once a week watering with any spronkler system is going to be ok, just dont overwater at night, stick to early mornings. I applied 10/10/10 in a circle about 1 foot out from the tree bole in early spring, and then again early summer, because my red clay is very acidic, hence the 10/10/10. Nice basic nutrients. 5. Don't flip out about the cancer issues that you might tend to google; you are planting a long term resource for shade and beauty and perhaps privacy, so pay attention to your trees....daily. If the branches are browning on the outside but green on the inside, that ok, it's just growth. If you see a ring around the trunk, then do some research, I won't go into detail here. Just watch your trees, and remember, if you are planting in a row or around fences/property, your soil may be very different from one side to the other. The pic below is a recent one of my Leyland's after 3 years. They started out at about a foot. This is in PACKED Georgia red clay with lots of rocks. You may experience some growtg difference, but if they look healthy, they are healthy. I must say: Your initial soil preparation is huge. Plant them well. The GG's and Leyland's have a tap root that if given proper care, will grow deep and delve for nutrients. Out of 50 planted not one has died or had a problem. I am not a tree doctor nor do I play one on TV. I am...a lover of oxygen.

Up date. Bananas still looking good but the Mimosa seems to have a new disease problem that is wiping out the old plants round here. A root fungus of some sort. I still will attempt, have two now growing ... gone native on the place, to use the Mimosa as a coppice but doubt they will last long. May be able to use as a intro plant to break the ground up, add N and act as a fodder too while it lasts. Mike