Miscellaneous

Light Requirements

Light Requirements


Light Requirements

Succulent Plants Problems: Sunburn

Sunburn on a succulent plant shows the worst damage at the top and side facing the sun. Ridges are more likely to burn than valleys along…


How to Light a Landscape

Don't feel overwhelmed—there are a lot of types of lights and a lot of spaces to place them. One of the best things that you can do to scope out your own project it to grab a good, high-powered flashlight with a dimming optic and get out into your yard at night. Then, play with the light. See what looks cool, or what might not work as well.

Here's a look at the various landscape lighting effects you might want to try:

Up Lighting

Used as an accent to architectural details and add safe passage to dark stairs, deck and step lights are installed directly into a yard's hardscape or decking. They can also be used for washing light down stone walls, lighting up entertainment spaces.

Up lighting is one of the most basic forms of landscape lighting. It is used to create drama with a taller structure or tree. You can choose to highlight the trunk of (generally larger) trees, or the underside of the tree's canopy on larger or smaller trees.
Use with: Spotlights, Well Lights

Silhouetting

This is a fantastic effect for highlighting dramatic shapes you might have hiding in plain daylight. Place the light source behind the item, and light toward where the main vantage point will be, making sure that the light source itself cannot be seen.
Use With: Spotlights, Well Lights.

Shadowing

This is the reverse technique of silhouetting. Placing the light between the main vantage point and the item being lit, with the light source aimed at the item. This really only works when you have a wall or flat surface behind the item being lit to catch the shadows created. But it can create a bit softer, more moody effect.
Use with: Spotlights, Well Lights, Flood lights

Moon Lighting

This is an especially effective way of using lighting when you have larger trees in your space. The light source is placed high up in the tree aimed down, washing the branches and ground below in light. It creates an impressive effect when used with an open-branched tree. (Photo via Kichler Lighting)
Use with: Spotlights

PRO TIP

Have an extra-large tree that deserves a special treatment? Giants, especially evergreens, can look amazing when you double-team them with lighting. Get both a spotlighting and a moonlighting effect by placing two spotlights half- to three-quarters of the way up the tree. Aiming one light up and one light down will create a dramatic effect, and the year-round foliage will hide the light sources.

Grazing

This can be a great option if you have a hardscape-heavy yard. Grazing involves placing the light close to the flat surface and aiming directly up or down the surface to create dramatic light and shadow play. You can graze up or down, but the idea is to take advantage of a texture across a flat plane, so uneven or irregular patterns work best. This can add an upscale touch, as it is often seen in hotel and restaurant design.
Use with: Well Lights, Hardscape Lights

Washing

Sometimes a space will need more ambient lighting. To create a well-lit space, try flooding a large wall or hedge in an entertainment area with light, which will “wash” the space with light. Use a wide-beamed light placed between the main vantage point and the surface to cast an even, gentle light over the whole area. (Photo via Hinkley Lighting)
Use with: Flood Lights

Technical Tips

Lumen output for landscape lighting can be subjective—it depends on how brightly you wish to illuminate any particular element. Look for fixtures with adjustable lumen output, so you can control the brightness yourself.

LED lighting is the new standard for landscapes, with lower operating costs and longevity that can’t be beat. Plus, new LED lights have features you will want to take advantage of, like adjustable beam spread.

And don’t snooze on color temperature. The best lighting for your landscaping should be in the same color family as the objects you’re lighting up: Use warmer light on oak trees and brown siding, while cooler colors like those found on pine trees or dark gray exterior stone play better with a more neutral color temperature. Very cool whites (4000-5000K) are best suited to ultramodern or commercial landscape projects. See our guide to color temperatures for more.

Go Forth & Have Fun

Now you have the basics to go forth and lay out your own landscape design. It's important to note that it's still important that you consult with a professional when laying out your landscaping plan so they can ensure you're working with the right voltage for your transformer and other important details.

The key is to take your time. And you can start small and build from there—an over-lit space can be as uncomfortable or unusable as a completely dark one.

There are a million ways to light your landscape, but the fun is in creating a unique look that reflects your own personal taste and lifestyle.

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Free Shipping
on orders of $75 or more!*

Orders of $75 and more:
You pay no shipping fees (UPS or FedEx ground) to anywhere in the continental United States. Nice!

*There are a few exceptions, though:

  • Special order, oversized and heavy items may need to be shipped by freight, and a freight shipping surcharge may be applied.
  • Also, some manufacturers require that we add a shipping surcharge to their products. When this is the case, you will see the shipping or freight charge listed on the product page.

Orders less than $75:
Orders that do not meet the $75 threshold are charged a $9.99 flat rate shipping fee.

There are a few exceptions, though:

Hawaii, Alaska & Puerto Rico
If you are shipping to Hawaii, Alaska or Puerto Rico, Lumens offers discounted standard shipping by UPS or FedEx standard shipping. The actual shipping charge (which at minimum is $24) will be calculated during checkout and is based on the order total.

Canada
When shipping to Canada, Lumens only uses Expedited and Express Saver which includes the brokerage fees in the shipping charge. All taxes and customs duties are listed at checkout and collected along with your order payment. Freight shipping may be required for heavy or oversized items, which includes large lighting fixtures and furniture. Freight shipping takes 7-10 business days, in addition to any lead time stated on the product page. All pricing displayed across the site is in US Dollars.

NOTE: Some manufacturers may require additional lead time for shipments to Canada. You'll receive an email with your expected shipping time frame if this is the case with your order.


Indoor lighting for houseplants involves:

  • Understanding how light affects plants
  • Discovering the different types of light exposure
  • The position or location of your lighting and plants
  • When and how to use artificial lighting
  • Diagnosing problems in struggling plants
  • Choosing the right plants for the type of lighting in your home

Keep reading to understand how plants use light, how to understand the lighting in your home, and how you can use it to help your plants grow best. After reading this, you’ll be able to move your plants around your home to meet their light requirements as well as choose the best plants for the lighting you already have in your home. You’ll also be able to identify and respond to lighting problems early, to keep your plants in great condition.


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Defining Sun Requirements for Plants

Shedding Light on Sun/Shade Conditions

By Dennis Patton, horticulture agent

As gardeners there is a lot to know when caring for our plants. We have been told the key to success is right plant, right place. That phrase is easy to say but has a lot of elements to dissect in order to create a lush beautiful garden. Soil, water, fertility, and, maybe the most misunderstood of all, light exposure.

Defining sun requirements
We have all picked up a plant tag and read needed light requirements — sun, part sun, part shade or shade. What does that all mean? It is enough to just make you want to throw up your hands and walk away. Understanding light exposure or sun/shade patterns is not easy but with a little help we might be able to shed a little light on this topic.

Light patterns is really about understanding microclimates in our garden and then finding the right plant that will thrive in the right spot. Increasing hours of sunlight in the Kansas City area means heat, while shade conditions may be 10 to 15 degrees cooler and more humid. Plants have adapted over time to favor a particular condition for best growth. It is our challenge to mimic these conditions if we want the most from our investment.

Full sun
Full sun is pretty easy for most of us to grasp but it becomes a little cloudier when determining the levels of shade. Full sun is direct summer sun for six or more hours per day. In nature full sun would be the meadows or open prairie spaces. In our KC backyards we define full sun as at least six hours or more of sun each day.

Shade — light, partial, full and dense
Shade is more complicated. It's about varying degrees of relief from the sun. Shade might be easiest to define if we break it down into four classes from light to dense shade.

Light shade can be defined as receiving between three and five hours of direct sun in the summer. Light shade may be the best growing conditions in our brutal summers here. These locations are sunny enough that many sun loving plants will grow while many shady lovers can still make it. Keep in mind that morning sun, which is cooler and less intense, is easier on shade loving plants then the hot afternoon sun. Plants that receive too much intense light will scorch if pushed into too much hot sun.

Partial shade is often defined as an area that receives two hours of direct sun each day or shaded for at least half the day. Here again, remember the difference between morning and afternoon sun and its effects on some more shade loving plants. Partial shade is good for many flowering shrubs that will produce more blooms with a little sun. These would include such plants as azaleas, rhododendrons and macrophylla hydrangeas.

Partial shade can also be found under or around trees. This is hard to determine but these conditions can exist under or near trees that have less than 50 percent canopy. It can also be found in the reflections of light off of buildings. Another way to look at partial shade would be more cooler morning sun and little or no hot afternoon sun.

Full shade is the third type of shade. These areas take in less than an hour of direct sunlight each day. It could also be dappled light through a tree canopy for most of the day. Full shade is not just a result of trees but also buildings, fences and other structures that cast shadows or block the sun rays.

When planting in full shade soil moisture can be an issue. Dry shade presents additional challenges for plant selections as the competition with tree roots can be high. Plants in this area should not only be shade tolerant but also drought tolerant unless supplemental water will be applied.

Dense shade is the last in this category. It which means no direct sunlight and little indirect light seldom reaches the ground. This would be the light under evergreen trees or overhangs of buildings. It can be found under shrubs, decks and dark corners and passages between houses. The ground is usually dry and dark from lack of light.

Dense shade is the most difficult and limiting growing condition. Plant selections are few due to the combination of shade, root competition, and dry soil conditions. Decorative mulches or ground covers are good alternatives for areas with dense shade.

What does the plant need? Read the tag.
Understanding the sun and shade patterns of the garden is only part of the equation. The second part is understanding the plant needs. Here again this can be confusing as plants can adapt to several light levels. The adaptation is related in many ways to the intensity of the sunlight. Remember morning sun is cooler and less intense. It does not lead to leaf scorch and stress. Some plants can tolerate a lot more sun if it was morning sun as opposed to the hot, scorching afternoon sun.

Plant growers try to help us figure out the needs. Many times on a plant tag there will be references to light requirements. Tags will say such things as sun, sun – part shade, shade. It can also get confusing as another tag can say shade – part sun. So what does that mean when several light levels are listed?

Here is the simple key to understanding the tag. The first word describing the light requirement would be the plants preferred location. For example "sun – part shade" means the plant will grow best in full sun but tolerate some shade. While a tag reading "part shade – sun" would prefer less sun or maybe morning sun over hot afternoon sun. Does that make sense or are you still in the dark?

Another problem we face in determining light levels is where the plant was produced and who rated its sun and shade tolerances. Full sun in Seattle or Minneapolis is really not the same intensity as full sun in Kansas City or Oklahoma City. Here in Kansas City our hostas scorch with hot afternoon sun. Head north and you will see them happy as a clam in full sun. It all goes back to intensity the difference between morning and afternoon sun. Ample soil moisture can help compensate for the effects of the sun on plant growth.

I feel like I have maybe confused you more than I helped. Understanding sun/shade patterns is not easy. But with a little thought, and good old trial and error you can soon figure out what is right for your favorite plant. One last thought. You planted in too much sunlight or shade? The solution is simple, just transplant to a new location. Weren’t plants meant to be planted on wheels as they seem to just keep shifting locations in the garden?

Have questions? The Garden Hotline is staffed by trained EMG volunteers and Extension staff who will assist you with questions.


Before getting a plant or starting seeds, determine the quality and hours of natural light in your space. Then choose plants with light requirements that match your indoor environment.

While a plant may tolerate lower light growing conditions, more light may be required to promote dense foliage and flowering.

Low light

(PPF: 50-150 umol m-2s-1 / 50-250 foot-candles / 10-15 watts)

  • A low-light plant would be suitable for a north window or a fairly dark corner.
  • Low-light plants require little to no direct light. In their native growing environments, these plants are “understory plants” meaning they grow underneath the branches of larger plants.
  • Low lighting is not sufficient for starting seeds indoors.
  • In environments with less light, plants grow more slowly and use less water. Avoid overwatering by feeling the soil.

Medium light

(PPF: 150-250 umol m-2s-1 / 250-1,000 foot-candles / 15-20 watts)

  • A medium-light plant would be suitable for east-facing windows or located near a west-facing window, but out of direct light.
  • You would need artificial lighting for starting seeds in medium light.
  • Like the low light plants, these plants will not dry out as quickly. Avoid overwatering by feeling the soil.

High light

(PPF: 250-450 umol m-2s-1 / more than 1,000 foot-candles, more than 20 watts)

  • A high-light plant would be suitable for brightly lit locations such as south- or southwest-facing windows.
  • You may be able to start seeds without artificial lighting, but seeds that need more time indoors, such as tomatoes and peppers, may become leggy without extra light.
  • High-light areas can be warm, making plants dry out faster. Check these plants more frequently and water when soil is dry.

Houseplants for different indoor light conditions

Just like choosing plants for sunny or shady areas of your outdoor garden, it’s important to choose plants that will grow in the existing light conditions indoors. And you may decide to add artificial grow lights to increase light energy to your plants.

The following houseplants are listed under the light conditions that provide the best indoor growing environment.

Low light is often loosely described as a light level "bright enough to read a newspaper." Most low-light plants are grown for their foliage, not flowers.

A low-light plant would be suitable for a north window or a fairly dark corner. In their native growing environments, these plants are "understory plants" meaning they grow underneath the branches of larger plants.

  • Chinese evergreen (Aglaonema)
  • Cast iron plant (Aspidistra)
  • Ponytail palm (Beaucarnea recurvata)
  • Parlor palm (Chamaedorea)
  • Dumb cane (Dieffenbachia)
  • Dracaena
  • English ivy (Hedera helix)
  • Sentry or kentia palm (Howeia)
  • Homalomena
  • Pothos (Epipremnum)
  • Philodendron
  • Lady palm (Rhapis excelsa)
  • Snake plant (Dracaena trifasciata formerly Sansevieria trifasciata)
  • Peace lily (Spathiphyllum)
  • Arrowhead plant (Syngonium)
  • Zee zee plant (Zamioculcas)

These plants grow well indoors in areas that are well-lit such as in east-facing windows or near a west-facing window, but out of direct sunlight. You’ll often find medium-light plants in spaces where fluorescent lights are on all day such as an office building.

  • Amaryllis (Hippeastrum)
  • Elephant ear (Alocasia)
  • Norfolk Island pine (Araucaria)
  • Asparagus fern (Asparagus)
  • Ferns
  • Rubber plant (Ficus elastica)
  • Fiddleleaf fig and weeping fig (Ficus)
  • Begonias (Begonia)
  • Spider plant (Chlorophytum)
  • Grape ivy (Cissus)
  • Aucuba leaf (Aucuba Japonica)
  • Croton (Codiaeum)
  • Jade plant (Crassula)
  • Flame violet (Episcia)
  • Schefflera (Schefflera)
  • Wax plant and Hindu rope plant (Hoya)
  • Peperomia (Peperomia)

High light areas are brightly lit locations such as south- or southwest-facing windows. As a rule of thumb, most plants grown for their flowers require high-light growing conditions.

  • Cacti and succulents
  • Citrus such as calamondin orange, kumquat, Meyer lemon
  • Hibiscus
  • Culinary herbs such as basil (Ocimum), thyme (Thymus), lavender (Lavandula)
  • Ti plant (Cordyline)
  • Orchid cactus (Epiphyllum),
  • Gardenia (Gardenia)
  • Jasmine (Jasminum)
  • Kalanchoe (Kalanchoe)
  • Geraniums (Pelargonium)
  • Poinsettia (Poinsettia)
  • Non-hardy azalea (Rhododendron)
  • Orchids
  • Caladium

Adding artificial lighting

Artificial lighting can be added to make up for the lack of natural sunlight. Once you have an idea of the available light in your space and the plants you’d like to grow, you may decide to add supplemental lighting.

The most common types of lighting include LED and fluorescent bulbs, but you may see incandescent and high-pressure sodium bulbs when shopping around. There are pros and cons to using each type, and all can be found at local hardware stores or online.

LED (light emitting diode)

  • Very energy efficient
  • Long-lasting
  • Wide spectrum of light
  • Do not produce too much heat
  • Wide variety of styles and sizes

Fluorescent

  • Moderately energy efficient
  • Cheaper up-front cost
  • Some only produce light in the blue-green spectrum, but others have a wider spectrum that includes red light check the label

Incandescent

  • Energy inefficient
  • Create heat
  • Do not last as long (in some cases)
  • High far red light causes plants to stretch

High-pressure sodium and metal halide

  • Emit substantial light over a wide surface area
  • Most commonly used commercial light source
  • Better for large-scale systems due to large size need to be hung at tall heights
  • Older technology
  • Release a lot of heat
  • Not all of the light is usable to plants

Factors to consider when you evaluate light

Light intensity

Light intensity is the brightness of light. The amount of light produced by a bulb is measured in a variety of ways and, unfortunately, two different bulbs may report their light output using different measurements, making it hard to compare. The distance between a light source and a plant impacts the light intensity.

While there are many ways to measure light, a few common measurements you are likely to see include:

  • PPF (photosynthetic photon flux) is a measure of how much plant-usable light is released by a bulb per second and is measured in micromoles of light per meter per second (umol m-2s-1). You may also see 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 a 1-square-foot surface located one foot away from a light source equal to one candle. It’s not used as frequently though you may find this measure in older reference books.
  • Lumens are less relevant when considering lighting for plants. Lumens measure how bright the light is to the human eye, and do not measure some of the important wavelengths that plants need to grow.
  • 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 intensity such as PPF, lumens or foot candles. A more efficient lightbulb will produce more light with fewer watts of energy.

Distance from light source

Keeping sufficient distance between plants and a light source is especially important when using bulbs that produce a lot of heat, like incandescent and high-pressure sodium. But even with LED and fluorescent lights, maintaining a proper distance helps to ensure healthy plant growth.

  • Seedlings: 4-6 inches (move your light up regularly as they grow)
  • Hydroponic lettuce and herbs: 6-12 inches
  • Foliage houseplants: 12-24 inches
  • Flowering houseplants: 6-12 inches

Light quality

Light quality refers to the wavelength or color of light. The light spectrum is composed of red, orange, yellow, green, blue, indigo and violet light. Sunlight provides all colors of light.

The part of the light spectrum that plants use is called Photosynthetically Active Radiation, which is composed of primarily red and blue light.

As lighting technologies have become more efficient, grow lights that only emit light from the red and blue wavelengths of the light spectrum have become more common.

Check the packaging to see what type of light is emitted by a grow light before buying it grow lights tend to be labeled as blue, red, or white/balanced light.

  • Blue light or mixed light bulbs are suitable for starting seeds and leafy greens, as well as non-flowering house plants.
  • Red light or mixed light bulbs are suitable for promoting bud formation in flowering plants as well as keeping the plants shorter.
  • White lights or mixed/balanced light bulbs are suitable for most plants at any stage of growth.

Light duration

Light duration (photoperiod) is the number of hours of light a plant needs per 24-hour period. Plants are classified by photoperiod into three categories for flowering response: short day, long day, or day-neutral.

  • Short day indoor plants, such as chrysanthemum, Thanksgiving and Christmas cacti and poinsettia, require short days to flower. You cannot reflower them indoors unless they are grown in short days.
  • Long day plants, such as African violets, gloxinia and tuberous begonias, flower when the daylight exceeds the hours of the night period.
  • Day-neutral plants are insensitive to day length differences for flowering and include indoor plants such as flowering maple (Abutilon), Crossandra, and gerbera daisies.

Use a timer to provide supplemental light if growing in a location with less natural light. Set your timer so that plants receive the following total light hours.

  • Seedlings: 16-18 hours per day
  • Hydroponic lettuce and herbs: 12-14 hours per day
  • Foliage houseplants: 12-14 hours
  • Flowering houseplants: 14-16 hours

Authors: Julie Weisenhorn and Natalie Hoidal, Extension horticulture educators

Reviewer: Neil Anderson, horticulture professor


Watch the video: What Bright Indirect Light really means: using a Light Meter. House Plant Journal