It depends on the community in which the building is located. Some have ordinances or laws restricting the placement of plants on buildings. It also depends on the construction of the building. It needs to be strong enough to hold all the extra weight of the growing medium and plants. If you check with the building owner, he or she should be able to tell you if it's allowed.
they are epiphytes, they depend on the plant they're growing on.
Top soil
You cannot grow plants in sawdust because plants do not and will not grow in wood. They need top soil. Actually you can grow plants in sawdust, wood chips, gravel or polystyrene beads if you wish using a system called Hydroponics. The sawdust etc are just there as an inert substance to support the root structure of the plant, while all its nutrient requirements are added to its water supply. This system is used commerically for growing many plants, including tomatoes. It has the advantages of being totally controllable and the inert growing mediums can be rendered disease free.
top soil
Competitive pressure. To get the energy that the sun provides, plants need to be able to "see" it. If another plant grows on top of the first plant, it will block the energy and the first plant will not grow as well. Natural selection would take care of the rest... those plants that can see the sun (those growing towards the sun and those that are taller) will prosper.
what type of plants would you expect to find growing at the top of the Sierra Nevada's peaks
they are epiphytes, they depend on the plant they're growing on.
The best type of soil for growing these plants is sand and top soil mixed with a little vitamin d.
Top soil
No, it is called permafrost, which is a top layer of frozen soil. It is bad for growing plants which is one reason that there is not many plants in the tundra.
Most plants grow from the top but grasses are different, they grow from the base so cutting or animals grazing does not stop them growing.
Because it's a mixture of decaying vegetation and minerals, and holds a lot of mosture - which make it ideal for growing plants.
They are called "buildings" regardless of what is on tip of them.
Yes it is illegal.
well, all plants compete for the most amount of sun by growing taller to be at the top and also by grwoing large leaves because its the leaves which soak up the sun.
they teleport up there
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