I F a seed is to sprout, it must be kept warm and moist, and when the little plant starts to grow it must have the food it needs. For plants eat. Every living thing eats. Plants have mouths in their tiny rootlets down in the ground and in their leaves. They must have good food in the earth for their roots to eat.
A boy named Johnny planted his seeds in the hard and stony corner by the front steps. His little sister Molly planted hers in a corner of the garden. Johnny's seeds scarcely sprouted. Molly's came up quickly. Their father said: "Johnny, your seeds are starving, that is the trouble. They need better food." So Johnny planted some more seeds in the garden and they sprouted well. Soon a great many little green plants came up with the young flowers.
"These," father said, "are weeds; you must pull them up."
But Molly said, "They are such pretty little things I shall leave them."
Johnny pulled the weeds out of his garden as fast as they came up, but Molly let hers alone.
After a while Johnny's garden was full of flowers. The plants were large and strong and covered with bright blossoms. It smelled sweet, and bees on gauzy wings buzzed about and gathered honey from the gay flowers, and butterflies danced over them and tasted the honey from their pretty cups.
And Molly's garden? There was hardly a flower to be seen in hers. The weeds had grown faster than the flowers and smothered them. The flowers were starved because the strong weeds had taken away the food out of the ground. They looked so small and puny that Molly felt like crying when she looked at them. "I thought the pretty little weeds had as good a right to grow as the flowers," she said. "But they don't play fair. They take everything. I am going to pull them up," and she caught hold of a big one and gave it a jerk. It came hard but it came at last. But with it came ever so many little portulacas—they were no bigger across than a penny although Johnny's portulacas were big, and all covered with gay flowers. Fourteen little portulacas came up with the roots of that big weed that had twined all among their little roots. But this isn't all. Back of the portulaca border was a border of sweet alyssum and six of them came up too, and back of the sweet alyssum was a border of sweet peas and three or four of them were also entangled in the roots of the weed.
"It is worse than I thought," said Molly in despair.
"Go slow!" said father.
So Molly pulled the next weed more carefully, but by the time she got the weeds all out Johnny said her garden looked moth-eaten. Only about half of her plants were left and they were tall, weak-stemmed things with few leaves and fewer flowers—they could not stand alone, having depended so long upon leaning against the weeds that were devouring them. But in time they looked better, although Molly's garden did not amount to much that season.
"Just wait till next year!" said Molly.
"Meantime, let us find out a little more about how plants grow," said the children's father, and they talked about it a great deal. Molly and Johnny were astonished to find that plants are really very particular about what they eat. That one kind of plant for instance grows best when there is a substance called lime in the earth, while another kind dies if there is lime. That some plants thrive best in sandy soil, while others cannot grow in the sand, that some need a great deal of moisture, while others can live only where it is very dry. Apples need a cold climate, oranges cannot stand frost; and so it goes. If we are to succeed with our plants we must know what kind of soil to plant them in, whether they like a shady place or a sunny place, whether they need to be kept moist or dry or hot or cold. And since they breathe we must give them plenty of clean air. Plants do not grow well in a house where there is gas or smoke in the room. Tobacco smoke will kill some plants very quickly.
"All these surroundings of the plant," father told them, "the food, the air, the light, the temperature, everything that influences its growth, we call by one word—environment. The success of the plant," he added, "depends upon its environment. If the plant does not do well we say there is something wrong with its environment, and we try to find out where the trouble is, and remedy it if we can."
Molly wanted to know if caterpillars and grasshoppers and snails formed a part of the environment of a plant.
"Yes," said father, "if those insects swarm in a region, that region forms a poor environment for plants to grow in. Anything that constantly harms or destroys makes a poor environment. A good environment is a place where everything helps instead of hinders."
"The greenhouse makes a good environment for our geraniums," said Molly.
"Yes, and a snow-bank would be a mighty bad environment for them," answered Johnny.
"Yet there are plants," said father, "that live under the snow and would die in the greenhouse."