Sometimes they come from trusted producers in other states. On a large construction job, such as a shopping mall, we may need 20 or more trees. Ornamental pots are available at garden centers and are often sold in bulk. They often come in both metal and wood.
Metal planters offer additional insulation against the elements and often have easy-to-install interior linings. Wooden planters tend to be more rustic and are used by people with less experience. Doug Delano (and Bill Hardy) opened Level Green landscaping LLC in 2002 to provide reliable commercial garden maintenance services in Washington DC, Maryland and Virginia. A good combined approach is often better when creating a landscape, even if a garden has never been planted before.
I'm sure that some people have a profit margin and also charge labor, but I've worked in the offices of several garden companies and most of them did it the way I described above. This is why it will be very difficult for you to get a good established landscape designer to help you. It's not unethical to buy your own plants and ask the landscaper to install them, but it's not effective unless you're a maintenance company or young children just starting out in business. The idea is that landscapers will generate additional sales for that nursery if they can buy at lower prices.
One of the most popular flowering shrubs in the United States, hydrangeas are a beautiful addition to any landscape. It is distinguished by its friendly and knowledgeable staff, including a landscape architect, New York State certified nurseries and experts in plant diagnostics. The fact sheets on native plants for gardening and landscaping (PDF) provide examples of native trees, shrubs, vines, grasses and flowers that work well in home gardens and landscaping. A gardening company often has a margin factor, which it charges, which includes selecting individual plants, bringing them to the site, organizing them, planting them, and securing the warranty.
If you're interested in landscaping and flower planting, or if you have experience with landscaping, you might be wondering where landscape designers get their plants from. Of course, it's not considered unethical, but I agree that not all landscapers would be comfortable or happy with this proposal. We've been designing and installing award-winning landscapes since 1928, whether it's a single tree or a complete remodel of your property.