INTRODUCTION

Every living thing progresses through a series of developmental stages, or life cycles, as it grows and matures. Plants begin as seeds, mushrooms as spores, insects and animals as eggs. It's easy to overlook these tiny first stages of life unless you know what time of year to look, where and how to search, and what to look for.

Once you start paying attention to the many lives being lived all around you, you probably won't want to stop! Every year we feel a sense of wonder as healthy vegetables grow from the tiny seeds we sprinkle. We're fascinated by the fragile seedlings we nurture as they become tall sunflowers, providing food for songbirds, squirrels, and chipmunks. Again and again we're filled with awe and astonishment when we witness a metamorphosis from egg to caterpillar to chrysalis and then watch a butterfly emerge and take flight.

You can begin your discovery of life cycles by just looking outside.

SEASONAL Cycles

You may not have thought of it this way before, but every garden — whether it's a tiny city park, a roof garden, a big backyard, or a thousand-acre farm — goes through life-cycle stages. Each season affects it in a different way, creating a separate and unique identity and purpose.

1 In spring, plants, insects, and animals that have been dormant through the winter awaken as the days get longer and warmer.

2 The summer garden comes alive with creatures hunting for food and raising their young. Plants and trees produce leaves and flowers that help feed hungry caterpillars, rabbits, and deer.

3 In the fall, as daylight hours begin to wane, chlorophyll gradually disappears from plant and tree leaves, revealing vibrant reds, oranges, and golds. Some insects migrate; others prepare for their own kind of hibernation.

4 In winter, most plants drop their leaves, and trees and perennial plants send nutrient-rich sap down to their roots for storage. Insects store sugar in their bodies that acts like antifreeze in their blood, preventing their cells from bursting and keeping them alive during cold weather. Insects that overwinter in their adult form, such as ladybugs, find a sheltered area and hide there until spring.

PLANT LIFE Cycles

The broad seasonal changes that go on in every garden are easy to see. But each plant also has its own developmental stages that you can discover when you look more closely.

1 Seed. Every flowering plant begins as a seed. Each seed contains an embryo.

2 Germination. Water causes the seed to swell and germinate, bursting out of its hard coating. Oxygen gives the seed energy until its leaves develop.

3 Growth of shoots and roots. The stem and seed leaves push upward toward light. Roots push downward, absorbing water and nutrients and anchoring the plant.

4 Flower development. The plant gradually shifts its emphasis from stem and leaf growth to reproduction, developing flowers.

5 Pollination. Pollen grains contain male genetic information, equivalent to sperm. Insects transfer pollen from one flower to another. If pollen is deposited on the receptive female part, called the pistil, the flower is fertilized and produces seeds.

6 Seed development. Seeds grow inside the pistil, which eventually becomes the seedpod or fruit.

Protect Those Pollinators!

More than 80 percent of the world's flowering plants need insects or animals for pollination, the process by which plants reproduce. Bees, beetles, butterflies, moths, and flies are some of the best insect pollinators there are. Bats and hummingbirds are also very valuable for pollination. Without these insects and animals, production of fruits, vegetables, and nuts — foods we depend on to survive — would be threatened.

That's why we always encourage people to garden responsibly. Here are two important ways to protect the pollinators in your garden.

LIMIT OR DISCONTINUE YOUR USE OF INSECTICIDES. Some of these poisons can kill not only the targeted insect pests they were formulated to eliminate, but also butterflies, honeybees, and other vital pollinators. Insecticides can make all parts of a plant toxic, including the nectar.

AVOID FILLING YOUR GARDEN WITH HYBRID PLANT SPECIES. Many hybrid flowers are genetically altered or selectively bred to produce certain colors, bloom sizes, or other traits. Unfortunately, this may result in flowers that have no pollen, nectar, or fragrance — the very things that insects and hummingbirds require.

Honeybees can fill the pollen baskets on the sides of their hind legs in just a few minutes. They bring the pollen back to their nest to use in making honey.

Many insects transport pollen from one plant to another as they search for nectar. The transfer of pollen enables the plants to make seeds.

SOIL LIFE CYCLES

Believe it or not, even the soil in your garden has a life cycle. The more you understand it, the better soil you'll have, and the better gardener you're likely to be. By "soil," we mean topsoil, the layer of earth that contains the nutrients and organic materials needed to produce vigorous, healthy plants. Many life-forms play a role in producing topsoil.

1 A plant dies.

2 Microbes move in. The decomposition process begins immediately. Microbes are microscopic organisms, such as fungi and bacteria, that attack and break down organic matter.

3 Decomposers go to work. Insects, snails, slugs, and worms also work on the dead plant, helping decompose it as it passes through their digestive tracts.

4 Water and warmth contribute. Rainfall and warm temperatures support and speed the decomposition process.

5 The plant becomes...