The Nine Major Requirements for Plant Growth

Day Length

• Plants need a certain amount of daylight for dormancy, development, flowering and growth. Plants use the length of the day as a cue for when to start growing in spring and when to prepare for dormancy or rest for winter. Many plants need a specific amount of daylight to flower.

Light

• Plant varieties vary as to how much light is needed, but light is a vital energy source for plant growth. Through photosynthesis, plant leaves absorb the light and convert that energy to starch and sugar, which satisfies the energy needs of the plant. Plants will either need full sunlight, partial shade and sun or all shade.

Space and Soil

• Plants need plenty of space for the roots and canopy to spread as much as the plant requires. If the root growth is restricted, plants will not grow to full maturity as intended. Plants need adequate soil depth for the roots to grow downward or spread to the sides. The soil must have good drainage and aeration so the roots can grow easily. For example, a medium-size tree would require about 300 to 400 cubic feet of room and soil to grow.

Water

• Water is an important requirement for plant growth. Some plants need more water than others, but some can tolerate periods of drought. If the water used on plants is high in salt or alkalinity, plants will have poor growth because of an imbalance in nutrients. The salt and high pH can prevent the roots from absorbing nutrients from the soil.

Atmospheric Conditions and Minerals

• Plant roots need oxygen to uptake nutrients from the soil and carry it to the entire plant. Soil may need to be aerated to let some oxygen into the ground, but plants growing in water will need a device to make the water bubble, which adds oxygen to the water. Plants need minerals to grow. Sulfur, magnesium, calcium, potassium, phosphorus and nitrogen are supplied in the form of a water-soluble or slow-release fertilizer. Some plants need micronutrients such as copper or iron, which would be supplied in a fertilizer formulated to include these important minerals.

Temperature

• Temperatures need vary among the different plant varieties, but some plants cannot tolerate temperatures that are too low, while some plants cannot handle high temperatures. Orchids for example, need daytime temperatures of between 70 and 90 degrees Fahrenheit, but temperatures at night must be at least 10 to 15 degrees Fahrenheit cooler for successful growth and flowering.

Insects

• Houseplants aren’t affected so much by lack of pollination, but vegetable plants, fruit trees and other flowering plants outdoors need insects for pollination. If you use insecticides on these plants to keep insects away, pollination will not take place unless the tree is self-pollinating and the wind is sufficient for dispensing the pollen to the entire plant.