A rule of thumb of choosing what size of container to use
Seeds, seedlings or starts = seed trays, community pots, or 4-6 inch pots
Cactus, succulents, orchids and other very slow growing plants = select a pot that breathes. like clay or concrete, or put extra holes in the sides of plastic pots. Select a pot that just accommodates the roots with 1-2 inches of room to spare to accommodate 1-2 years' growth.
mature plants under 12 inches = 1 gallon
plants 2-3 ft = 5 gallon
plants over 3 ft = 18 gallon or 20-24 inch pots
Shallow rooted = select a pot that is wider than it is deep.
Basic soil mix
1 part peat moss
1 part perlite
1 tablespoon of slow release fertilizer (osmocote, nutricote) per gallon of mix
Soil mix for wet plants
1 part peat
1 part compost
1 part vermiculite
1 part perlite
horticultural charcoal in small amounts
1 tablespoon slow release fertilizer per gallon of mix
1 part NZ bark
1/4 part large perlite
dusting of dolomite lime
slow release fertilizer 1 tsp per pot
Orchid Mix 2
Med size black cinder or no. 3 blue rock
1 tsp slow release fertilizer per pot
Orchid Mix for vandas and rootless orchids
Small clay pot or basket that just keeps the plant upright
Styrofoam to wedge plant in place
tie wire to tie plant to basket.
Tie vanda to basket to keep it upright, Wedge with one or two pieces of large styrofoam to keep plant stable. Hang it up and water daily
To save rootless cuttings =
place cuttings or bulbs in a clean pot with a little loose sphagnum pot at the bottom. Pot should just be large enough to keep the plant upright. Water as needed transplant when roots 1/2 inch long
Oncidiums, vandas, catleya, and bromeliads can be grown in pots without media. Plants need to be wedged in place by selecting a pot small enough to just hold them upright and wedging the plant with pieces of broken pots or styrofoam. Water lightly daily and use water soluble fertilizer.
Succulents, orchids, anthuriums, citrus trees will grow well in cinder. Cinder provides good aeration, but no nutrients so regular fertilization and water is required. Cinder is heavy, so do not plan to move pots often unless they are on dollies.