The Incense Cedar is a good choice. However, they will grow tall and in time lose their lower branches. From the pictures it looks like you get a fair amount of rain. Your heading says zone 6. So, I have some suggestions. First get rid of the cottonwoods. Personally, I hate them and their cotton. Whit firs (Abies concolor) would be good choices for screening, especially if interplanted with incense cedar. Western Red Cedar (Thuja plicata) would also be a good screen plant. They keep their branches all the way to the ground. The Sierra Redwood (Sequioadendron giganteum) would be one to seriously consider. Yes, they grow 300 feet tall and 30 feet in diameter, but not in your lifetime. They grow rapidly and in a normal human lifetime will get about 50-75 feet tall and around 3 feet in diameter trunk. The spread would be about 20 -30 feet. They will keep their lower branches for many years. Also, they are quite prickly to reach into and will discourage unwanted visitors in that way. My best advice would be to plant a mixed row of all these. Being as they are evergreens they will not have super deep roots and being planted together they help to support each other in high winds. The snow load is not a problem for these trees. They are all cold hardy in zone 6. The Thuja has several different regional varieties. If you go for them, make sure the parent stock is from inland varieties as the coastal varieties are not cold hardy in your zone. These trees are all available online and you can probably get them in small tubes for large scale, economic planting.

I think we paid about $40 for one, two years ago, that was about 6-1/2' tall. It is now about 9' to it's tallest point. I do agree that the Poplar will sucker. We had some at our old house that suckered quite badly after we moved them. Wherever the root got even slightly scratched, up popped a new tree. Suckers are new shoots of the tree, appearing either near the base of the tree or sometimes quite a distance from the tree. Many, many trees will sucker, though. The Swedish Aspens don't seem to do that so badly, although they still will produce some. You should be able to buy some small ones - 4' - 5' - for about $15 - $20. Remember, they do grow fairly quickly. A bit of a trade-off, though, is that the columnar aspens, generally, do not have lower branches. So the tree has quite a tall trunk, about 30" - 36", which have no branches. Appearance-wise, I'm OK with them, but some people don't like that. My husband really likes them because the mower goes around them really well. He's one of those "non-gardener" types that likes things really, really easy. Dear man, though. I'll keep him.

Euphorbias seem to make a nice hedge/screen. I have red euphorbias that are about 6-7' tall right now, and they have beautiful red foliage year-round, but they don't fill in super full. Maybe I'm just not pruning them harshly enough though. I have a neighbor who butchers hers every few months and they always come back like gangbusters! I also have a hedge of Mexican pointsettia. I haven't been able to find out the official name of this plant. None of the pictures that come up on the web show what this plant is, but that is what it is called in all the nursuries I have seen it in here. It has small leaves, about 1 1/2" X 1/4", but it fills out nicely, better than the red euphorbia for a screen. In the winter (about November-February), the leaves all turn white, and it has a very delicate smell that is reminiscent of almond-flavored things. I have had my plants in the ground for about a year, and they are about 4' tall. I don't know if they are going to get much taller or not. If you look in the nurseries now, you could probably still find these with some of their white leaves. We are about 1/4-1/3 mile away from the ocean, so we get a little salt spray but nothing extreme. I'm sure a good nursery would be able to tell you about the salt tolerance. Both plants seem pretty drought-resistant, and I haven't had any trouble with bugs on the red euphorbias. The Mexican poinsettias do attract whitefly, but it doesn't seem to cause any real problems. Happy gardening!

Wow, I like your bravery. I was lucky enough to be raised by gardening parents and grandparents, so I had the headstart of absorbing their knowledge as I grew up. Search the web for a used copy of a book called "Crockett's Victory Garden" He was from Boston -- very similar climate -- and did a PBS television show, and did a book each on flowers, vegetables, and houseplants. Full of practical advice from a lifetime gardener, long since dead. Some notes for next year. Peat pots: ignore the manufacturer's proud claim that you can set them right in the ground. It causes plants to get root bound and prevents them from flourishing. If the roots have grown through by the time you plant them, carefully pull away the peat anyway. The disruption will prevent the plants from getting root bound in the ground. When they start growing new leaves, it means the plants have settled in. If you unpot a plant from the garden center and can see roots all around the root ball, slash through these roots vertically and pull away the severed pieces of root (same on bottom side). This will allow new growth out into the surrounding soil. A trick with tomatoes: Most people don't know they can grow roots from their stems. If you start them indoors and they get long and leggy, replant them deeper with half of their stem buried. If they are still too tall and the weather still too cold, cut to tops off milk cartons (and punch a drainage hole in the bottom) and bury the stems in those. When they go into the ground, you can even lay them on their side and gently bend so only the top four or five inches are above the soil. This will give a large root system that will help them endure dry spells. A trick with long season plants (like cantaloupe): buy seedlings, and plant in dark colored containers that retain heat. They are from a hot climate, and the dark container will warm the soil, especially in the cool shoulder seasons, and that will make them happier. Mediterranean herbs: These need a Mediterranean micro climate. Find fast-draining bagged soil mix meant for cactus, succulents and palm trees. It may be in a specialty corner in your garden center, with houseplants. Use this soil in terra cotta or other earthen pots, (never in glazed or plastic pots, as these hold too much moisture). Give them all the sun you can, but be careful not to let them go completely dry in hot dry spells. This treatment will succeed with rosemary, thyme, oregano, sweet marjoram, nepatela (a.k.a. cat mint, not cat nip), chives, lavender, and you can also do this with nasturtiums if you grow those for salads. When I lived in Maine, I used 1-foot wide pots with three rosemary plants each in a south window all winter. In spring I set them in the ground and used them for cooking, while I got new plants for the pots, nursed them along on the doorstep. In fall I brought in the pots, and let go of the ones in the ground (but coastal Maine they lasted almost to Thanksgiving). Depending on our windowsill space and your favorites, you can try this with any of those herbs, but lavender will not cooperate. Not all herbs are Mediterranean. Basil originated in southern India, and flourishes in heavy soil and hot humid weather. Dill and tarragon and mint and cilantro are from cooler climates and flourish in the milder part of year, and dill and cilantro go to seed as soon as the weather turns hot. Most of these do fine in plastic pots that hold more moisture. Mint is almost a marsh or stream plant, so it likes a lot of sun and a lot of water. Lay plank walkways between your rows to prevent soil compaction. Cultivate to keep weeds at bay (a claw with a five-foot handle will save your back). If you skimmed the sod, the grass likely will come back. If weeds become a problem, you can start a new season by covering the garden with black plastic, and cutting out planting holes in it. Laying plank walkways over it to keep it from blowing away. The two most space-intensive crops are peas and corn. And corn is a massive nutrient hog, a waste of space for a single ear per massive plant. If you must have peas, snow peas will give you much more food for the room they take up, but need to be planted as soon as the soil is thawed. Corn (and a lot of other vegetables) are the reverse: if they are planted in cool soil, their growth will be permanently stunted for the entire season. No kidding; my father did a controlled experiment with corn and beans and learned this not something to rush no matter how anxious you are. If you have trouble with big tomatoes, try cherry tomatoes in a future year. i've moved from Maine to the Sonoran Desert, so now I am a beginner again for the first time since I was ten (and that was fifty years ago!). I grow lots of herbs, but don't even attempt any vegetables except peppers. They have a long season requirement, so try them in dark containers too. Good luck. You are at the start of a great adventure that is guaranteed to have some failures and setbacks along with the little triumphs that keep us at it!