A soil that actually is more like a mulch would be recommended. Miracle Gro makes a great potting soil specifically for orchids. Its called Miracle Gro Orchid Potting Mix.
I think the best soil for all crops is loamy soil
The best soil that wheat will grow in is loamy well-drained soil. This type of soil has equal parts clay soil particles, sand and silt.
Loam soil
sandy soil
Topsoil is generally best, however soil type and quality will depend largely on the types of crops you're raising. Soil PH is a big factor in determining which plants will do well in your climate and soil type.
Plastic generally helps hold in moisture. Depends what kind of plant you are repotting. Unless it's in the miniature category you can use from a 4 inch size pot. Keep in mind that if the plant you're repotting is a flowering type it's best that you don't plant it in a huge pot because it might not flower. Some varieties like their roots compacted.
I think the best soil for all crops is loamy soil
The best soil that wheat will grow in is loamy well-drained soil. This type of soil has equal parts clay soil particles, sand and silt.
Every plant has different soil needs; there isn't one type of soil that is the best for all plants.
FDXGFDDG
Loam soil
sandy soil
The best type of soil for growing these plants is sand and top soil mixed with a little vitamin d.
Orchid
fertizlalied soil or good soil and dry soil
sandy soil
humus amd poting soil