By LINDA G. TENNESON, Master Gardener

Birds do it, bees do it, but how do flowers and trees do it? How do plants reproduce themselves? Just like some birds have colorful feathers to attract a mate, some plants have colorful flowers so they can attract the helpers that are needed in the reproduction process. Flowers may be beautifully colored and/or fragrant so that outside helpers will make a visit and then spread the plant pollen from one flower to another. There are also plants with rather plain flowers because they can pollinate themselves without outside help.
Flowers come in different types with some containing both male and female reproductive parts. There are also flowers with only male or only female reproductive parts. In addition, there may be both male and female flowers growing on the same plant or only on different plants. Sweet corn, squash, melons and cucumbers have male flowers that bloom first and then female flowers which bloom a few days later. Plants that have only male or only female flowers need the help of the wind, insects, birds or other animals to move the pollen from one flower to the other. Fruit trees fit into this third category. Apple trees must be planted near other apple trees in order to obtain fruit. There are also a few “oddballs” that have both male and female flowers on the same plant but the plant is self-sterile; that is, the female flower will not be able to form a seed without pollen from a separate plant.
The whole reason for flowers to exist is to produce the next generation. Seeds are the equivalent of babies in mammals. However, in plants the seed must be produced and then left some place where it will have a chance at germinating and growing to full size to produce the next generation.
Like mammals, flowers have ovaries containing the eggs needed for reproduction. The ovary is located deep in the middle of the flower. The male reproductive organ is the stamen which contains a pollen sac that is located on the end of a filament. The filament holds the pollen sac up where the wind can catch the pollen or insects or animals can brush against it. Think of the long stamens in the middle of the Easter Lily blooms that drop orange dust on the white petals or on anything else they touch. That orange dust is the pollen that is needed to fertilize the egg in another lily bloom. After an egg is fertilized it develops into a seed.
If the pollen is to be moved by the wind, the flower will not be as showy because it is not necessary to attract a pollinator. However, those flowers that are colorful, fragrant or contain nectar have these characteristics so that insects, animals or birds will approach, pick up the pollen and then move it to another flower. Flowers that are popular for butterfly gardens are those that need the help of a butterfly in order to move the pollen from one bloom to another. Hummingbirds that visit many flowers to drink their nectar are also spreading pollen from bloom to bloom as they do their feeding.
Once the egg and pollen get together, they form a seed. The seeds may develop inside a shell that later breaks and spreads the seeds several feet away from the parent plant. Seeds that are found in fruits need the help of a person or animal to eat the fruit and then to leave the seed core on the compost pile or on the ground so that the seed becomes exposed to soil and can germinate. Other fruits have their seeds on the outside like corn and strawberries. They all rely on the process of being food for a mammal and so being moved away from their parents in order to grow in a new location.
Did you ever think that when you looked at flowers and seeds in your garden that you were watching “G” rated sex?

Garden sex is not the only thing you can learn about plants by going to the Beltrami County Master Gardener Web site, www.extension.umn.edu/county/beltrami/mg/index.html. You can also read this article and previously archived ones. You can access University Extension information directly by going to www.extension.umn.edu/gardeninfo.