How does light affect different growth stages?
Written by
Julia Anderson
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Light is fundamentally responsible for every stage of plant growth from germination until harvest. Its intensity, duration, and spectrum initiate the necessary biological functions of flowering and photosynthesis. Plants can be kept in underwater conditions, and seedlings may fail to thrive or fruit can be suppressed by inadequate light. To achieve the desired results, it is important to use the correct light requirements for each stage of plant growth. This will ensure easy and proper plant production and health.
Germination
- Indirect light prevents seed dehydration while allowing warmth absorption
- Photosynthesis begins once cotyledons emerge above soil surface
- 12-16 hours daily exposure establishes strong initial growth
Vegetative Stage
- Blue spectrum light (400-500nm) promotes leaf and stem development
- Minimum 6 hours direct sunlight or equivalent artificial intensity
- 18-hour photoperiod maximizes growth for many vegetable crops
Flowering Transition
- Red spectrum light (600-700nm) triggers bud formation and blooming
- Photoperiod-sensitive plants require specific day/night cycles
- 12-hour darkness period essential for short-day flowering plants
Improving light exposure helps avoid growing problems. The use of reflective mulch during the vegetative growth period helps reflect the light onto the lower leaves of the plants. Rotating growing containers daily ensures even exposure, preventing lopsided or unbalanced plants. I put adjustable LED lights above my seedlings when I noticed weak stems. This simple change helped tremendously.
Seasonal changes necessitate adjustments to lighting practices. Summer requires shading for sensitive plants, while winter requires supplemental lighting. Timers should be installed to maintain constant photoperiods throughout the year. Light intensity should be measured weekly with inexpensive PAR meters. These practices ensure that plants receive the proper amount of illumination throughout their life cycle.
Read the full article: 6 Plant Growth Stages Explained Simply
