HTML
Interior Plant Environment - Printable Outline
LHAP 303-61-40682 (FA25) - Softscape Maintenance/Interior Plants/Interior Plant Environment - Printable Outline.html
Resource Viewer
Preview or play this resource here.
Extracted Text
Extracted from the original source file.
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>The Interior Plant Environment - Printable Outline</title>
<style>
:root {
--ink: #1e252b;
--muted: #56616b;
--line: #ccd5dd;
--accent: #2f6f73;
--soft: #eef6f4;
}
* {
box-sizing: border-box;
}
body {
color: var(--ink);
font-family: Arial, Helvetica, sans-serif;
font-size: 11pt;
line-height: 1.42;
margin: 0;
background: #f7f8f7;
}
main {
max-width: 8.5in;
margin: 0 auto;
padding: 0.5in;
background: #fff;
}
h1,
h2,
h3,
h4 {
color: var(--accent);
line-height: 1.18;
margin: 0;
}
h1 {
font-size: 23pt;
border-bottom: 3px solid var(--accent);
padding-bottom: 0.15in;
}
h2 {
font-size: 16pt;
margin-top: 0.3in;
padding-bottom: 0.05in;
border-bottom: 1px solid var(--line);
}
h3 {
font-size: 13pt;
margin-top: 0.22in;
}
h4 {
font-size: 11.5pt;
margin-top: 0.14in;
}
p {
margin: 0.08in 0;
}
ul,
ol {
margin: 0.06in 0 0.1in 0.24in;
padding: 0;
}
li {
margin: 0.035in 0;
}
table {
width: 100%;
border-collapse: collapse;
margin: 0.12in 0;
font-size: 10pt;
page-break-inside: avoid;
}
th,
td {
border: 1px solid var(--line);
padding: 0.07in;
vertical-align: top;
}
th {
background: var(--soft);
color: var(--accent);
text-align: left;
}
.subtitle {
color: var(--muted);
font-size: 12pt;
margin-top: 0.12in;
}
.section-note {
border-left: 4px solid var(--accent);
margin: 0.12in 0;
padding: 0.08in 0.12in;
background: var(--soft);
}
.two-column {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 0.14in;
}
.keep {
page-break-inside: avoid;
}
@page {
size: letter;
margin: 0.45in;
}
@media print {
body {
background: #fff;
}
main {
max-width: none;
padding: 0;
}
h2 {
page-break-after: avoid;
}
h3,
h4 {
page-break-after: avoid;
}
.section-note,
table,
.keep {
break-inside: avoid;
}
}
</style>
</head>
<body>
<main>
<header>
<h1>The Interior Plant Environment</h1>
<p class="subtitle">Printable outline for the PowerPoint presentation by Travis Letwiniuk</p>
</header>
<section>
<h2>1. Temperature</h2>
<table>
<thead>
<tr>
<th>Temperature Range</th>
<th>Guideline</th>
</tr>
</thead>
<tbody>
<tr>
<td>Low</td>
<td>4 - 18 C</td>
</tr>
<tr>
<td>Medium</td>
<td>13 - 21 C</td>
</tr>
<tr>
<td>High</td>
<td>16 - 30 C</td>
</tr>
</tbody>
</table>
<p>These are guidelines for the amount of heat a plant requires to develop normally.</p>
<p>This assumes that all other environmental factors are also in the appropriate range.</p>
</section>
<section>
<h2>2. Light</h2>
<div class="section-note">
<p><strong>Light is the most important limiting factor in plant growth.</strong></p>
</div>
<h3>How Light Influences Plants</h3>
<p>Light influences the plant's environment and its biochemical and physiological processes in many ways:</p>
<ul>
<li>
<strong>Photosynthesis</strong>
<ul>
<li>Low light can inhibit growth even if all other necessities of growth are present.</li>
</ul>
</li>
<li>
<strong>Chlorophyll synthesis</strong>
<ul>
<li>Green pigment in plants.</li>
</ul>
</li>
<li>
<strong>Temperature</strong>
<ul>
<li>Light warms the surface of plants.</li>
</ul>
</li>
</ul>
<h3>Light Wavelengths and the Color Spectrum</h3>
<p>Light is emitted from its sources in various wavelengths.</p>
<ul>
<li>Light energy or wavelengths fall within 400 - 700 nanometers (NM) (PAR), which are important for plant growth.</li>
<li>
Visible light, the light we see, falls within PAR.
<ul>
<li>However, PAR extends out past the visible range into the far red, infrared, and ultraviolet.</li>
</ul>
</li>
</ul>
<h3>Three Basic Light Characteristics</h3>
<p>When it comes to light in plant growth, there are three basic characteristics to look for.</p>
<ol>
<li><strong>Quantity:</strong> intensity or brightness.</li>
<li><strong>Duration:</strong> day length.</li>
<li><strong>Quality:</strong> color.</li>
</ol>
<p>A plant's response to all of these varies by the species.</p>
<p>Balancing plant light requirements is an important factor.</p>
<h3>Light Intensity: Quantity</h3>
<p>Quantity of light refers to:</p>
<ul>
<li>The amount of light energy the plant receives.</li>
<li>
Brightness of light is measured in:
<ul>
<li>Foot-candles (FC) or lumens.</li>
</ul>
</li>
</ul>
<p>Example: On a sunny day in the greenhouse, a crop could receive 10,000 foot-candles of light.</p>
<p>On a cloudy day, especially during winter, light levels are much lower.</p>
<p>When light intensity levels are low, supplemental light is required.</p>
<h3>Supplemental Light for Low-Light Plants</h3>
<p>Plants with low light requirements can be grown in areas with no natural light, but with the use of a combination of cool white and warm fluorescent tubes.</p>
<ul>
<li>New tubes can provide up to 1000 foot-candles when the plant is 6 - 12 inches away from the source.</li>
<li>Lights are left on for 14 - 18 hours per day.</li>
</ul>
<h3>Two Ways to Look at Light Quantity</h3>
<ol>
<li>
<strong>Illumination or photometric</strong>
<ul>
<li>A measurement of visible light level, as seen by the human eye.</li>
<li>Measured in foot-candles or lux/lumens.</li>
</ul>
</li>
<li>
<strong>Irradiation or radiometric</strong>
<ul>
<li>Looks at all energy from a light source.</li>
<li>Measurement is focused on the wavelength range of 400 - 700 nm.</li>
</ul>
</li>
</ol>
<p><strong>Note:</strong> This is the region that corresponds with PAR.</p>
<h3>Light Intensity Rating Guide</h3>
<p>The following rating is given as a guide to the light intensity needed by a particular plant in foot-candles.</p>
<table>
<thead>
<tr>
<th>Rating</th>
<th>Foot-Candles</th>
<th>Foot-Candles Per Day</th>
</tr>
</thead>
<tbody>
<tr>
<td>Low</td>
<td>25 - 75 f.c.</td>
<td>300 - 2400 f.c./day</td>
</tr>
<tr>
<td>Medium</td>
<td>75 - 150 f.c.</td>
<td>2400 - 6000 f.c./day</td>
</tr>
<tr>
<td>High</td>
<td>150 - 1000 f.c.</td>
<td>6000+ f.c./day</td>
</tr>
</tbody>
</table>
<h3>Too Much or Too Little Light</h3>
<ul>
<li>Too much light can be as damaging as too little light.</li>
<li>Plants exposed to very high light are susceptible to scalding and will not photosynthesize properly.</li>
</ul>
<h3>Minimum, Recommended, and Ideal Light</h3>
<h4>Minimum</h4>
<ul>
<li>At this light intensity, a plant will not be able to produce energy to maintain itself over the long run.</li>
<li>Over time, it will have to be replaced.</li>
</ul>
<h4>Recommended</h4>
<ul>
<li>The level at which the plant will be able to replace old leaves as they die.</li>
</ul>
<h4>Ideal</h4>
<ul>
<li>This intensity will provide the plant with enough light to replace old leaves and put on new growth.</li>
</ul>
<h3>Factors That Affect Light Intensity in the Interior Plantscape</h3>
<p>In the interior plantscape, the intensity of light is dependent on a number of factors.</p>
<ol>
<li>
<strong>The source of light</strong>
<ul>
<li>How far the plant is from the light source.</li>
</ul>
</li>
<li>
<strong>Obstructions</strong>
<ul>
<li>Blinds, curtains, posts.</li>
</ul>
</li>
<li>
<strong>Light reflected from surfaces</strong>
<ul>
<li>Texture of the surface.</li>
<li>
Color of the surface:
<ul>
<li>White reflects 90%.</li>
<li>Grey or beige reflects 50%.</li>
<li>Mirrors reflect 80 - 90%.</li>
<li>Drapes reflect 35%.</li>
</ul>
</li>
</ul>
</li>
</ol>
<h3>Symptoms of Incorrect Light Intensity</h3>
<p>Symptoms of incorrect light intensity depend on the species' light requirements.</p>
<table>
<thead>
<tr>
<th>Plant Part</th>
<th>Symptom</th>
<th>Intensity Too High</th>
<th>Intensity Too Low</th>
</tr>
</thead>
<tbody>
<tr>
<td>Leaves</td>
<td>Defoliation, slow or rapid.</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td>Leaves</td>
<td>New leaves small.</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td>Leaves</td>
<td>All leaves yellow and dropping.</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td>Leaves</td>
<td>Leaf blade longer than normal.</td>
<td></td>
<td>X</td>
</tr>
<tr>
<td>Leaves</td>
<td>Leaf thin.</td>
<td></td>
<td>X</td>
</tr>
<tr>
<td>Leaves</td>
<td>Petiole longer than normal.</td>
<td></td>
<td>X</td>
</tr>
<tr>
<td>Leaves</td>
<td>Petiole shorter than normal.</td>
<td>X</td>
<td></td>
</tr>
<tr>
<td>Leaves</td>
<td>Loss of variegation.</td>
<td></td>
<td>X</td>
</tr>
<tr>
<td>Leaves</td>
<td>Reduced holes in split leaf plants.</td>
<td></td>
<td>X</td>
</tr>
<tr>
<td>Leaves</td>
<td>Leaves very thick.</td>
<td>X</td>
<td></td>
</tr>
<tr>
<td>Leaves</td>
<td>Leaves may scorch or sunscald on the edge or center.</td>
<td>X</td>
<td></td>
</tr>
<tr>
<td>Leaves</td>
<td>New leaves bleached, curled, and will not return to normal.</td>
<td>X</td>
<td></td>
</tr>
<tr>
<td>Leaves</td>
<td>Shade-loving plants develop chlorosis, become very brittle and thick, and chlorophyll is damaged.</td>
<td>X</td>
<td></td>
</tr>
<tr>
<td>Stems</td>
<td>New growth leggy.</td>
<td></td>
<td>X</td>
</tr>
<tr>
<td>Stems</td>
<td>Few lateral branches.</td>
<td></td>
<td>X</td>
</tr>
<tr>
<td>Stems</td>
<td>Elongated stems and wide internodes.</td>
<td></td>
<td>X</td>
</tr>
<tr>
<td>Stems</td>
<td>Dead stem tissue.</td>
<td>X</td>
<td></td>
</tr>
<tr>
<td>Stems</td>
<td>Leaves close and stems thicker than normal.</td>
<td>X</td>
<td></td>
</tr>
</tbody>
</table>
<h3>Duration: Photoperiod</h3>
<p>Duration refers to the total measure of accumulated light over one day and is also known as photoperiod.</p>
<p><strong>Houseplant lighting explained further:</strong> Growers will supplement or cut off light to control maturation.</p>
<ul>
<li>This is called photoperiod control.</li>
</ul>
<h3>Photoperiod Response</h3>
<ul>
<li>
Changes naturally with the season.
<ul>
<li>Has a definite effect on plant growth.</li>
</ul>
</li>
<li>
The longer the photoperiod, the more time there is to photosynthesize.
<ul>
<li>Therefore, more energy is available for growth to take place.</li>
<li>Plants make their greatest amount of energy with long days and short nights.</li>
</ul>
</li>
</ul>
<h3>Plant Signals from Changing Photoperiod</h3>
<p>When photoperiod is reduced or lengthened, it sends signals to plants to respond in different ways.</p>
<p>It may induce:</p>
<ul>
<li>Dormancy.</li>
<li>Abscission of leaves.</li>
<li>Setting of buds.</li>
</ul>
<h3>Main Photoperiod Responses</h3>
<ol>
<li>
<strong>Short-day response</strong>
<ul>
<li>Plants will only go into the reproductive phase under a shorter day or long night situation.</li>
<li>They will flower when they receive less than 12 hours of bright light.</li>
<li>Absolutely all light must be blocked out.</li>
</ul>
</li>
<li>
<strong>Long-day response</strong>
<ul>
<li>Plants will only go into the reproductive phase under a long day or short night situation.</li>
<li>They will only flower when they receive more than 12 hours of light.</li>
</ul>
</li>
</ol>
<h3>Quality: Color</h3>
<p>Visible light is made up of several wavelengths, each individual wavelength possessing a certain color.</p>
<ul>
<li>When you look at visible light from the sun, it appears white.</li>
<li>If you look at it through a prism, the light is broken up into its separate wavelengths, which you can see as different colors.</li>
</ul>
<p>The majority of light for plant growth is in the visible light spectrum.</p>
<p>The measurement and comparison of this color spectrum is known as quality.</p>
<ul>
<li>While all wavelengths within PAR are required, some wavelengths are more important than others.</li>
<li>While plants are sensitive to one or more wavelengths, the human eye is sensitive to others.</li>
</ul>
<h3>Foot-Candles and Lux Lighting Terms</h3>
<p>Foot-candles and lux measure the same thing: the amount of visible light that falls on a surface.</p>
<p>The difference is that the foot-candle uses the Imperial standard measuring system, such as feet and pounds, while lux uses the metric system, such as meters and grams.</p>
<p>A single foot-candle is equivalent to the amount of light that falls on a surface that is one foot away from a single candle, and a lux is the amount of light that falls on a surface one meter away from a candle.</p>
<p>For conversion: 1 foot-candle = 10.764 lux.</p>
<h3>Additional Tips for Indoor Lighting</h3>
<ol>
<li>
Know your plant's light requirements.
<ul>
<li>Low, medium, high.</li>
</ul>
</li>
<li>
Purchase a light meter.
<ul>
<li>Inexpensive option: Amazon Dr. Meter.</li>
</ul>
</li>
<li>
Read this article for additional ways to measure light for plants.
<ul>
<li>Greenery: Unlimited.</li>
<li>This will ensure the area is receiving the required light levels.</li>
</ul>
</li>
</ol>
<p><strong>Note:</strong> If you are used to working with lux or are using an instrument that only measures lux, there is a direct conversion between the two units of measurement.</p>
<p>1 lux = 0.0929 foot-candle.</p>
<p>You can multiply your total lux by 0.0929 to get your foot-candle measurement.</p>
</section>
<section>
<h2>3. Water</h2>
<div class="section-note">
<p><strong>Water is essential for plant growth.</strong></p>
</div>
<ul>
<li>
In the interior plantscape, temperature is fairly consistent.
<ul>
<li>Therefore, the rate of transpiration is lower.</li>
<li>Water requirements will be lower.</li>
<li>Time of year will affect water uptake.</li>
</ul>
</li>
</ul>
<h3>How Often to Water</h3>
<p>There are no standard rules that will tell you how often interior plants will need to be watered.</p>
<p>How often you have to water is affected by a number of factors:</p>
<ol>
<li>
The physical environment:
<ul>
<li>Light intensity and duration.</li>
<li>Air and soil temperature.</li>
<li>Relative humidity (RH).</li>
<li>Drafts.</li>
</ul>
</li>
<li>Age of plant.</li>
<li>Type of plant.</li>
<li>Size of plant.</li>
<li>Size and composition of the container.</li>
<li>Water-holding capacity of the growing medium.</li>
<li>Soluble salt content of the growing medium.</li>
<li>Plant growth activity, including time of year.</li>
<li>Condition of the root system.</li>
</ol>
<h3>Deciding When It Is Time to Water</h3>
<p>It is important not to overwater, as this reduces the oxygen available to the roots and increases the chance of disease.</p>
<ul>
<li>
On the other hand, never let the media dry out.
<ul>
<li>A plant should never be allowed to wilt.</li>
</ul>
</li>
<li>
A plant may wilt for other reasons:
<ul>
<li>Overwatering, overfertilizing, and excess salts can also cause wilt.</li>
<li>Wilting can happen from low RH, bright light, and high temperatures.</li>
<li>Root rot.</li>
</ul>
</li>
</ul>
<p>Before you water, make sure watering is required.</p>
<p>The best way to do this is to touch the soil, look at the medium, and know how much the plant needs.</p>
<h3>Watering Guidelines by Species</h3>
<p>Watering guidelines depend on the species.</p>
<table>
<thead>
<tr>
<th>Moisture Level</th>
<th>Guideline</th>
</tr>
</thead>
<tbody>
<tr>
<td>Very moist</td>
<td>Do not let the media go dry between waterings.</td>
</tr>
<tr>
<td>Moderately moist</td>
<td>Allow the media to go slightly dry between waterings. The amount of drying will depend on the species.</td>
</tr>
<tr>
<td>Moderately dry</td>
<td>Allow the upper level of the media to dry between waterings.</td>
</tr>
<tr>
<td>Dry</td>
<td>Allow the media to dry almost entirely between watering.</td>
</tr>
</tbody>
</table>
<h3>Moisture Meters</h3>
<ul>
<li>Moisture meters can be added to help with determining watering needs.</li>
<li>Moisture meters should not be used alone.</li>
</ul>
<h3>How Much to Water</h3>
<ul>
<li>
When watering plants in containers with drainage holes:
<ul>
<li>Enough water should be used to thoroughly wet the entire growing medium.</li>
<li>Allow for some drainage out the bottom of the container.</li>
</ul>
</li>
<li>
Shallow watering will encourage roots to grow only in the top portion of the container.
<ul>
<li>Small amounts of water will result in a buildup of salts in the medium.</li>
</ul>
</li>
</ul>
<h3>Watering Methods</h3>
<h4>Leach Irrigation</h4>
<ul>
<li>Involves watering from the surface, allowing the water to percolate down through the medium.</li>
<li>
Medium should be thoroughly wetted each watering.
<ul>
<li>About 10% of the water should wash through the root zone into the drainage area.</li>
<li>Ensures soluble salts are kept low enough to maintain long-term root health.</li>
</ul>
</li>
<li>
Some issues to consider:
<ul>
<li>
Compacted and settled soil:
<ul>
<li>Leach irrigation may result in overwatering.</li>
<li>Root-bound plants have the tendency to be overwatered or underwatered.</li>
</ul>
</li>
</ul>
</li>
</ul>
<p><strong>Important:</strong> Never allow the plant to sit in the water that has leached through the medium during watering.</p>
<h4>Subirrigation</h4>
<ul>
<li>Water seeps into the media through capillary action from a reservoir at the base of the planter or planting bed.</li>
<li>Allows wicks or other means to move water upward.</li>
<li>Requires less day-to-day attention and provides stable soil moisture if managed properly.</li>
<li>Monitor soil salts closely.</li>
<li>Use good quality water.</li>
<li>Replace compacted soils immediately.</li>
<li>Use mulches to reduce surface evaporation.</li>
</ul>
<h3>Water Temperature</h3>
<ul>
<li>
Ideally, water temperature should be at least equal to the leaf temperature.
<ul>
<li>5 C warmer will help speed up water absorption.</li>
</ul>
</li>
<li>
Cold water cools soil temperature and slows water and nutrient absorption.
<ul>
<li>Cold water is also known to damage roots and leaves.</li>
</ul>
</li>
<li>Philodendrons and Sansevierias are examples of plants sensitive to temperature.</li>
</ul>
<h3>Water Quality</h3>
<h4>Soluble Salts</h4>
<ul>
<li>
The amount of soluble salts in the water is an important consideration when evaluating quality.
<ul>
<li>Water with low soluble salts can be used without any special practices.</li>
<li>
Water with medium salt content is usable only if special practices are followed:
<ul>
<li>Provide adequate drainage in the media.</li>
<li>Do not allow the medium to become more than moderately dry.</li>
<li>Do a soil test regularly.</li>
<li>Leach periodically to remove the excess salts that will accumulate in the medium.</li>
</ul>
</li>
</ul>
</li>
</ul>
<h4>Hard Water</h4>
<ul>
<li>
Hard water is high in calcium and magnesium salts.
<ul>
<li>Gradually increases the pH of the medium.</li>
<li>
If it sits on the leaves:
<ul>
<li>White, unsightly residue remains when it evaporates.</li>
<li>Residue is difficult to remove without a cleaning agent.</li>
</ul>
</li>
</ul>
</li>
</ul>
<h4>Soft Water</h4>
<ul>
<li>High-sodium water destroys soil structure.</li>
<li>Increases soil salt content.</li>
<li>Becomes toxic to plants.</li>
</ul>
<h4>Chlorine and Fluoride</h4>
<ul>
<li>
Municipal levels of chlorine are not likely to cause toxicity.
<ul>
<li>High levels, 5 - 10 ppm, may cause minor chlorosis in some species.</li>
</ul>
</li>
<li>
Fluoride may be injurious to some species.
<ul>
<li>It can cause brown, necrotic spots or lesions, especially in older leaves.</li>
</ul>
</li>
</ul>
<p>When fluoride damage is suspected, maintain higher soil moisture with aerated water or distilled water to dilute fluoride concentrations.</p>
<p>To minimize fluoride injury:</p>
<ul>
<li>Keep pH 6 - 6.5.</li>
<li>Allow irrigation water to sit open at room temperature for 24-hours.</li>
<li>
Avoid superphosphates or fluoride-containing amendments.
<ul>
<li>Perlite in the medium.</li>
</ul>
</li>
</ul>
</section>
<section>
<h2>4. Relative Humidity</h2>
<p>Relative humidity (RH) is the actual humidity of the air.</p>
<ul>
<li>
The warmer the air temperature:
<ul>
<li>The more water it can hold.</li>
<li>RH decreases.</li>
</ul>
</li>
<li>In Alberta in the winter, RH can be as low as 15%.</li>
<li>Some plants require 60% or more.</li>
<li>Most indoor plants are produced in an environment with much more moisture in the air than is found in the average home or building.</li>
</ul>
<h3>Ways to Increase Relative Humidity</h3>
<ul>
<li>Build a humidifier in with the heating system.</li>
<li>Install a misting system.</li>
<li>Group plants so moisture from transpiration creates a microclimate.</li>
<li>Use a tray filled with gravel or sand, sit plants on top, and fill with water.</li>
<li>Use a terrarium.</li>
<li>Place plants in areas where there is naturally more humidity, such as a bathroom.</li>
</ul>
<p><strong>Note:</strong> Misting needs to be done regularly to keep humidity up.</p>
<ul>
<li>May cause disease problems.</li>
<li>Increase air circulation to help the leaf surface dry quickly.</li>
<li>Mist in the mornings.</li>
</ul>
</section>
<section>
<h2>5. Media</h2>
<p>Whether you buy premixed media or mix your own, the ultimate goal is that the media fits the required criteria.</p>
<h3>Indoor Plant Soil Requirements</h3>
<p>Indoor plant soil requires these properties:</p>
<ol>
<li>Support: physically supports the plants.</li>
<li>Water-holding capacity.</li>
<li>Air spaces.</li>
<li>Nutrient-holding capacity.</li>
<li>
Stability.
<ul>
<li>Plants will be in the mix for a long time.</li>
</ul>
</li>
</ol>
<h3>Potting Mixes</h3>
<p>Different potting mixes are on the market, including specialty mixes like:</p>
<ul>
<li>Cactus mix and azalea mix.</li>
<li>
Often, mixes are peat-based media enhanced with:
<ul>
<li>Perlite.</li>
<li>Vermiculite.</li>
<li>Sand.</li>
<li>Composts.</li>
<li>Fertilizers.</li>
<li>Water crystals.</li>
</ul>
</li>
</ul>
</section>
</main>
</body>
</html>