HOW MUCH LIGHT DO I REALLY NEED?
How much light do I really need?
Did you know that plants are affected by too little or too much light. These two variables produce different results on your plants and some plants are more resilient and adaptive then others. While a plant may tolerate lower light conditions, more light could be provided to allow the plant to truly flourish. For example a Sansevieria “Snake Plant” can tolerate very low light as it’s often used in office spaces or as a beginner plant due to its ruggedness, but to truly see this plant grow healthy and beautifully it can be placed in a medium light location. You will see beautiful consistent growth and a very dense happy plant.
A plant with insufficient light takes on unique characteristics as its tries to adapt to the light given.
Plant stems become “leggy”, the stems become long creating spacing between nodes as the plant stretches for more light.
Variegated plants may revert to solid green leaves to increase the chlorophyll intake.
Flowering plants will not flower or produce flower buds with insufficient light.
Interior leaves thinning. (Turning yellow and dropping from the inside of the plant)
Fungus Gnats form
Soil stays too wet
A plant with too much light
Result in bleached/sunburned leaves
Drooping leaves/Dehydration
Unless it’s a variety of plant that truly loves the hot sun ex. cacti, succulents, birds of paradise, Ficus Benjamin, Hibiscus, Gardena, Citrus and etc.
The first question we ask is “How much light do you get?” in the prospect plant-parent room. Is it a north-facing window, west-facing, east facing or south-facing window? There are couple ways to figure the answer to this question. First is just noticing the time of day the light enters the specific room/ area. It’s a silly question, but not everyone notices the time the sun is coming into their rooms or living spaces, so I love pulling out my compass on my phone and directing through the window. Once I gather the direction of light I then eliminate other variables that could reduce the light intensity such as overhangs large tree’s that reduce light intensity and if windows have UV tints.
Let’s start by getting familiar with Low light, Medium Light, High light. As well as the terms used when placing them in your home as Bright Indirect Light is introduced depending the facing of the window and distance from window.
Low Light (PPF:50-150 mol m-2s-1/ 50-250 foot candles/ 10-15 watts) - would be a north facing window or a dark corner that still can cast a shadow. This means enough light is still entering the room and if you are able to read a book with out any artificial lighting a low light categorized plant would love its new home. North facing windows never receive direct sunlight.
Low light plants require little to no direct light. Fluorescent lights all day.
In their native growing environments these plants are understory plants so they grow underneath the branches of larger plants.
Areas that are considered low light traditionally use plants that grow more slowly and use less water. Making sure these beauties are loved with neglect, but set a reminder to check every 10 to 14 days to nail down a watering schedule for them.
Medium Light (PPF:150-250 mol m-2s-1/ 250-1,000 foot-candles/ 15-20 watts) would love an East-facing window or out of direct light in a west-facing window. Usually picking a place about half the distance from a window and back wall would receive medium light.
Ranging from bright indirect to partial or filtered light.
East or West facing windows range of 6 to 10ft away from window.
North facing windows 3 - 6 ft away due to the light intensity difference it can be closer to the window
High Light (PPF:250-450 mol m-2s-1/ more than 1,000 foot-candles, more than 20 watts)- would love a south or southwest facing window. Due to the intensity of southern light you must take couple other variables into account.
High-light areas can be warm, making plants dry out faster. Selecting a plant that likes to go dry and one that requires minimal watering would be best for a low maintenance high-light plant.
Require Direct or Strong sunlight for most of the day. Usually will be afternoon sun.
Bright Indirect Light - Easiest way I’ve figured what bright indirect light would be a place to the left or right of a window that faces East/West/South. It’s an area that gets no direct light but gets a steady bright source of light. For example orchids love a bright indirect location. This allows them to catch the filtered bright light but avoids the extreme heat of direct sun as that will burn the foliage and cause the orchid not to flower well.
Artificial Light - Using grow lights are a great way to extend your range of plants into areas that may not receive sufficient natural light. Once we figure the light in your space and the plants you’d want to add to your collection supplemental lighting can be added. There are many ways to measure light and a few common measurements you are likely to see .
PPF - (photosynthetic photon flux) is a measure of how much plant-usable light is released by a bulb per second and is measured in micro moles of light per meter per second (mol ms2-1). PPFD (photosynthetic photon flux density) which is a measure of PPF as it reaches a surface like a plant leaf. PPFD goes down as your plants get further away from the light source.
Foot-Candle is the amount of light received by 1 sq ft surface located one foot away from a light source equal to one candle. This unit of measurement isn’t as frequently used, but used in older reference guides.
Lumens are less relevant when considering lighting for plant, Lumens measure how bright the light is to the human eye, but plants are more concerned about the wavelengths of light and the full spectrum colors to help with growth.
Watts are a measure of the amount of energy needed to produce light, rather than a measure of the actual intensity of the light. Light bulbs should report both watts and another measure of light such as PPF, lumens or foot candles.
Maintaining proper distance helps ensure a healthy plant and the correct amount of light for the plant.
Foliage houseplants 12-24 inches - Total hours of light 12-14 hours
Flowering Houseplants 6-12 inches. Total hours of light 14-16 hours
Use a light timer to provide supplemental light if growing in a location with less natural light.
Ensuring it’s a full spectrum light so the plants receive all the colors necesssary from the light source to grow properly.
Gathering and learning all the possible variations of light strength will help create one of the most joyful experiences. being a plant parent. I remember when I purchased my first plant Rubber plant ‘Tineke Ruby’. I pulled out my phone and used my compass and I lit up when i realized my windows faced west, but I had large trees filtering my light coming in until 3pm. I decided to put my ‘Tineke Ruby’ right by the window to ensure she would get all the light she needed. She’s been doing great and now will be outgrowing its current container and location! lol good problems to have.