Posted September 2022

Floriculture Orchids

Floriculture Orchids

What is an Orchid
What is an Orchid?
The Santa Barbara International Orchid Show is put on by and for people who are orchid enthusiasts and experts, those who know the intricacies of orchid naming and cultivation. But for many of us, orchids are very pretty flowers that we have in our homes, see in grocery stores for sale, use as a corsage for a special occasion, or even, perhaps, see as an adornment on our dinner plate when visiting Hawaii! So what exactly is an orchid? The intent of this photo essay is to answer this question.

Orchids are plants that belong to species in the Orchid Family, or Orchidaceae. This family was considered to be part of the Monocotyledonous group, or "monocots", which have one seed leaf, or cotyledon, compared with "dicots, which have two seed leaves. Moncots include such plants as lilies, orchids, irises, grasses, and many aquatic plants. More recent research has indicated that the evolutionary tree is more complex than just dividing all plants into monocots and dicots, but orchids are still more closely related to families such as lilies and irises than to many other flowering plants.

It is orchid flower structure in particular that separates species in this family from other related plants. In most flowers there are four whorls of flower parts: sepals, petals, stamens, and pistils

  1. Sepals are on the outside of the flower, and serve to protect the flower when it is in bud form.
  2. Inside the whorl of sepals are the petals. Petals usually attract insects to flowers, effectively "flagging" them down. The say "get your nectar here!" in order to lure insect visitors that will move pollen from one flower to the next, and thus effect pollination.

What is an Orchid continued
What is an Orchid continued
  1. Within the flower, stamens form the next whorl. Stamens consist a stalk (the filament) and a sack-like structures that contains pollen (the anthers). Pollen in turn carries the the sperm cell, needed for fertilization and the making of seeds.
  2. The innermost whorl within flow ers is the pistil or pistils. Each pistil is composed of a stigma (where the pollen lands), the ovary (where the ovules or egg cells are; these will mature into seeds after fertilization), and a style that connects the stigma to the ovary.

In orchid flowers, there are (usually) three sepals, which protect the flower in bud, and three petals, but in orchids the petal that appears lowermost is usually very different from the other two, and is called the lower lip. It is either highly colored or ornamented with bumps which form a platform where insects can land, or it has a pouch or spur containing nectar.

What is an Orchid continued
What is an Orchid continued
The lower lip is one thing that differentiates orchid flowers from the flowers of other plant families. 'The other floral feature that makes an orchid an orchid is the column. In orchids, the stamens and pistils are not physically separate, rather they are fused into a special elongated structure called the column. 'There are no filaments of the stamens, and the anther sacs, called pollinia, resemble tiny yellow saddle bags. 'The ovary is inferior (occurring below the other flower parts), there is no style, and the stigma sits at the end of the column under the pollinia, which are covered by an anther cap.

What is an orchid? An orchid is a member of the orchid family with that particular flower structure just described. But to those of us who enjoy them, an orchid is a flower that brings much pleasure. Beautiful, exotic, often sweet-smelling. And there are lots of them! Greater than 20,000 native species exist, with species on every continent except for Antarctica. Most are tropical, especially those that have been brought into cultivation, but there are many temperate orchids that grow from lowland environments up into the subalpine.

Because orchids have adapted to pollination by many different and specific insects, the shape, size, color, and fragrance of flowers is incredibly diverse. And because of this diversity of flowers, and of course their beauty, orchids have been collected and cultivated for many years, resulting in over 300,000 different cultivars! These cultivated forms or genetic strains are sometimes merely based on selection within a species, or sometimes created from hybrids. Recently, with the advent of propagation using tissue culture, many popular hybrids are now intergenetic, that is, crosses between different genera of orchids. Several of the plants in the displays are intergenerie hybrids within a part of the orchid family called the Oncidhnae.

The listing of "fun facts" above shows many of the features common within the orchid family. Hopefully this photo essay will increase your enjoyment of orchids: perhaps vou can find some of the examples here in plant featured here in this show!

California Native Orchids
California Native Orchids
  • Fairy slipper orchid, Calypso bulbosa
  • Rein Orchid, Piperia elongata
  • California Lady Slipper Orchid, Cypripedium californicum
  • Stream Orchid, Epipactis gigantea

Cultivated Orchids
Cultivated Orchids
  • Cymbidium
  • Vanda alliance orchids

Orchids General Watering Tips
General Watering Tips
  1. Water in the Morning
  2. Lift up the pot
    If Light = Water
    If Heavy = Don't Water
  3. Water one or twice per week
  4. Hot sunny / dry windy days = increase water
    Cold gloomy days = decrease water

Orchids Fertilizer

Orchids Pollination
The complex mechanisms which orchids have evolved to achieve cross-pollination were investigated by Charles Darwin and described in his 1862 book Fetilisation of Orchids. Orchids have developed highly specialized pollination systems.

Orchids can be pollinated by bees, moths, butterflies, ants, insects, hummingbirds among other things. Pollinators are often visually attracted by the shape and colors of the labellum. The flowers may produce attractive odors. Although absent in most species, nectar may be produced in a spur of the labellum, on the point of the sepals or in the septa of the ovary.

In orchids that produce pollinia, pollination happens as some variant of the following. When the pollinator enters into the flower, it touches a viscidium, which promptly sticks to its body, generally on the head or abdomen.

While leaving the flower, it pulls the pollinium out of the anther, as it is connected to the viscidium by the caudicle or stipe. The caudicle then bends and the pollinium is moved forwards and downwards. When the pollinator enters another flower of the same species, the pollinium has taken such position that it will stick to the stigma of the second flower, just below the rostellum, pollinating it. After pollination, the sepals and petals fade and wilt, but they usually remain attached to the ovary. After the pod matures, it will split open and the seed will be dispersed.

Seed that lands in or on a suitable environment will sprout and eventually grow into mature plants. Possessors of orchids can take the place of "mother nature" and pollinate orchids with a pencil or toothpick.

Orchids Propagation Methods
Propagation Methods
Orchid propagation is acquiring multiple numbers of plants from the one plant. In general, there are six types of orchid propagation. They are: seed, meristem, keiki, top cutting, division, and backbulbs. Seed and meristem propagation are both laboratory methods. The other four methods are vegetative propagation, the easiest for the home grower or hobbyist.

This is an orchid propagation process best suited for the laboratory requiring a high level of sterility. The other reason is that orchid seeds are very fine particles that need special growing techniques because the seed has no nutrients in it to sustain the seedling during the initial growth.

This orchid propagation procedure takes place by removing plant tissue and replicating it in the laboratory. The procedure requires sterility and cleanliness of the highest degree. This is a process used to mass produce plants for the pot plant industry.

Keiki is a vegetative form of orchid propagation. It is the formation of new offshoots, baby stem or baby plants with roots from the base or stem of the plant itself. This is quite a common occurrence among many popular orchids such as vanda, phalaenopsis and dendrobiums. The plantlets can be removed from the base or stem of the plant when the plantlets have roots that are about an inch long. They are potted up and then grown on to mature plants.

Top Cutting
Many vandaceous orchids tend to grow very tall. As the plant grows tall it tends to put roots out along the stem in between the leaves. These can be divided by cutting off the top portion of the plant as long as the top portion has at least two pairs of roots attached to it. It is then potted up in its own pot. The bottom portion of the plant will probably form a keiki and is treated as mentioned above.

Division is basically a process of splitting the plant into two or more plants. The divisions should consist of three bulbs or more to insure blooming the following year. The divisions are potted into their own individual pots. A plant is usually divided after it has formed a number of bulbs or has outgrown its pot. The best time to divide a plant is usually after it has bloomed and is starting to grow new roots

Backbulbs are usually leafless bulbs that have already bloomed. The backbulbs are removed during the dividing process. Once the bulbs have been removed and cleaned up, they can be put in pots and sprouted.

Orchids Types
  • Phragmipedium
  • Ascocenda
  • Epidendrum
  • Phalaenopsis
  • Vanda
  • Phalaenopsis
  • Paphiopedilum
  • Coelogyne
  • Phalaenopsis
  • Brassia
  • Dendrobium
  • Brassocattleya
  • Dendrobium
  • Vanda
  • Cattleya
  • Phalaenopsis
  • Phalaenopsis
  • Oncidium
  • Dendrobium
  • Brassocattleya
  • Dendrobium
  • Brassavola
  • Encyclia
  • Phalaenopsis

Orchids Types

Orchids How Many Types
How many Orchids are there?
  • There are 20,000 species of orchids
  • There are 880 genera or orchids
  • One of the largest genera of orchids is Dendrobium with about 1,400 species
  • There are over 300,000 different orchid cultivars, and the number of cultivated strains is increasing daily with the advent of tissue culture techniques for propagating orchids.

Where do they grow?

  • Orchid species can be found from sea level to the alpine, and from the quater to the Arctic.
  • In California and the west, some orchids grow on the inhospitable serpintine.
  • One western American Native orchid is called a stream orchid (epipactis gigantea) the plants grow in streams!
  • Orchids can grow on the ground (terrestrial orchids) or on trees, as epiphytes.
  • Most cultivated orchids are epiphytes, which is why they are grown in orchid medium .. over watered.
  • Hawaii is famous for its orchids, but most are cultivars, not native orchids.
  • The native orchids of Hawaii are small green orchids like the Rein Orchids (piperia) from North America.
  • Bamboo Orchid (arundina graminifolia) is a "weed" in Hawaii.
  • Malayan Ground Orchid (spathoglottis plicata) is naturalized on some of the Hawaiian Islands (not native to these islands but established in permanent populations).

Orchids How Big How Small
How Big, How Small?
Orchids can be very large or very small, with single flowers, or with many flowers.
  • Orchids are never have true wood (as in hardwood trees).
  • Most orchids are herbs, but some are vines, such as Vanilla (vanilla planifolia).
  • Orchids often have a pseudobulb. This bulb-like structure is not a true bulb, rather it is a thickened part of the stem between the attachment point of two leaves. A true bulb is also a storage organ, but is formed by thickened leaf bases, as in an onion.
  • The orchid tree is not an orchid, rather it is a member of the Legume Family with f s that reminded someone of an orchid!
  • The Giant Orchid, Gram-matophyllum speciosum, has flowering stalks that can grow to a height of 3 meters, bearing up to 80 flowers, with each flower up to 10 cm wide.
  • The Green Bead Orchid, On-cophyllum globuliforme, has the tiny pseudobulbs that are less than 1 mm in size, and from each arises a tiny thread-like leaf.
  • Flowers of the native California species Piperia unalascencis are only a few millimeters in size.
  • Flowers of the native California species Cypripedium monta-num are several centimeters across.

Orchids Plant Protection
Plant Protection
  • Protect your plants from strong sunlight and heat
  • Use appropriate shade cloth
  • Water and mist several times a day

Low Light
Low light for orchids is about 1,000 to 1,500 foot-candles. This is the amount of light they would get naturally in the lowest levels of a heavily canopied tropical forest. Orchids such as Paphiopedilum and Phalaenopsis thrive in low light and will burn and fail to flower in higher light levels. In a greenhouse or shade house, use 70% to 80% shade cloth

Medium Light
Medium light orchids such as Cattleyas need about 1,500 to 3,000 foot-candles of light. This is the amount of light an orchid would get growing midway in the canopy of a tree where the branches begin to open up a bit. In the greenhouse or shade house, use 50% shade cloth.

High Light
High light orchids tolerate light levels of 3,000 to 4,500 foot candles of light. This is the amount of light that reaches the dappled shade of the uppermost canopy of a tree. Some high light loving orchids are Vandas and some Cattleyas. In the greenhouse or shade house, use 20% shade cloth.

Very few orchids like full sun all day

Measuring Light Levels
Measuring light levels for orchids takes some experience, but there are some ways to help. A light meter is the best way, but light meters can be expensive. An alternative is to use the shadow cast by your hand on a sheet of white paper 1 foot away. Full sun at noon in the summer is around 10,000 foot-candles, and your hand will cast a clearly defined dark shadow, under low light conditions, the shadow of your hand will be blurry, and it may be difficult to make out a distinct shape. Under medium light, you will have a clearly defined shadow that is slightly blurry. In high light conditions, the shadow will be dark and crisp, but not as defined as under full sun.

What is shade cloth and do I need it?
Shade cloth is a commercially available material for placing over your greenhouse or shade house to cool it in the summer and provide a lower amount of light. It is usually made of loosely woven polyester and can be found in varying densities or degrees of shade from approximately 5% to 95%.

If you live in a humid area, misting or fogging may not be enough to cool your greenhouse or shade house in the hot, humid summer months. When all else fails, you can create your own shade by using shade cloth.