Whether you need to grow plants fast for a science project during the holidays, or you’re interested in growing plants to gift for Mother’s Day or Teacher Appreciation Day, sometimes you just need a way to speed up the process.
If you’re cutting it close and you need an edge to cultivate plants fast and indoors, there’s a method you can use to stimulate plant growth.
The first of which starts with the type of plant you’re growing.
Some plants grow at much faster rates than others, given the conditions are right and proper care is taken.
Fast Growing House Plants
- Jade Plants
- Spider plant
- Pothos
- Chinese Evergreen
Mustard, cress, beans and sunflowers are among the fastest growing indoor plants most suitable for school science projects as the entire growth cycle can be documented over a two-week holiday.
For parents with impatient toddlers wanting fast growing indoor plants to grow from seed, herbs are the way to go. You can grow basil in four days, and/or dill and chives in a week to two weeks.
For reasonably speedy winter growth indoors (under a month), arugula is a vegetable plant taking preference to cooler temperatures. Mint’s another option, but that’s an invasive one that can quickly grow out of control.
The Indoor Conditions All Plants Need to Grow Successfully
Without the right interior conditions, you won’t be able to make indoor plants grow faster. What plants need are the right light conditions, proper temperature, relative humidity, nutrients, and water.
Light is the crucial factor that determines whether a plant will grow indoors, just tolerate the conditions (no growth but stays alive) or just flat out die.
Different species of indoor plants grow under low light, moderate light and high light. Plants that need high-light levels will grow slower in the United States because the U.S is on the Northern hemisphere, meaning most of the sunlight comes from the south.
That’s why it’s often advised that the best place to grow indoor plants is on the windowsill of a southern facing window.
How to Measure Light Indoors to Determine the Type of Plant to Grow
Light is most commonly measured in foot candles. The term ‘foot candle’ (abbreviated as ft-c or just ft), is a measurement of light intensity “produced by a source of one candle at a distance of one foot and equal to one lumen incident per square foot.”
If you have an iPhone, there’s a light meter app available. While not of professional grade, it can give you a decent indication as to the amount of light you have in different areas of your home, helping you decide on the most suitable location for your plant.
A digital light meter (LUX meter) can also provide an indication of the amount of light your plants will get indoors, however, that’s not all going to be usable energy for the plants.
Measuring light is best done with a PAR meter (Photosynethically Active Radiation) as it’s the PAR that contributes to photosynthesis, which is how plants grow. However, PAR meters are expensive, so these are really only an option for professional growers and not for kids experimenting or for a 2-week science project.
When you want to grow plants fast indoors, foot candles can give you a good ball park to aim for with your lighting. For best results, use quality indoor lighting, balanced with the right temperature and humidity levels.
You can learn more about growing plants indoors under artificial grow lights here.
When you buy your plant, the label will indicate the level of light it needs as being either low, medium or high/bright light.
As guidelines of light intensity levels…
- Low light requires at least 75 ft-c.
- Medium light requires at least 150 ft-c.
- High/bright light requires at least 300 ft-c.
If the plant needs direct full sunlight, it’s going to need 1,500 ft-c, which will be difficult to achieve without using indoor grow lights.
As an example of how light differs by plant type:
A snake plant needs a high level of light, or full sun, which means it’ll need about 5 to 6 hours a day of full sun. On a summer’s day at noon, full sun measures approximately 10,000 foot candles. Throughout the day, the ft-c will average to between 5,000 and 7,000-foot candles.
A Chinese Evergreen plant is a fast grower indoors under low light, normal temperatures and average humidity levels, therefore, a Chinese Evergreen is going to grow faster inside under normal light conditions from a south facing window, whereas a snake plant would need artificial lighting to help it grow.
For any indoor plant you’re planning to grow and want to do it fast, you can check the growing conditions on the Guide to Houseplants Encyclopaedia page. Click on the plant name you’re interested in, scroll down and you’ll see an at-a-glance list of growing conditions letting you know the temperatures, light levels, humidity and care tips for successfully growing the plant indoors.
Light level, temperature and humidity are the key factors which play a pivotal role in stimulating plant growth.
Plant Growth Stimulation
- 70oF is an optimal temperature for most indoor plants.
- Soil differs by plant species. For most plant varieties, a good quality potting soil has vermiculite, permite, and peat moss.
- The major component to stimulate faster growth is nitrogen. Plants need 16 nutrients to grow healthily. The main three are Nitrogen, Phosphorous and Potassium. All fertilizers are labeled with numbers indicating the amount of each as N, P, K. The first number is nitrogen and should be the highest number of all three. When all other nutrients are available in sufficient amounts, adding fertilizer with high amounts of nitrogen will significantly increase the speed of plant growth. The richest nitrogen plant feeds available are blood meal fertilizer (13-0-0).
The only other condition you need to have right in your home is the humidity level.
The vast majority of house plants originate from the tropics where humidity levels are high, often above 50%. You can measure the humidity in your home with a hygrometer. Ideal relative humidity levels for comfort are between 40% and 50%.
High humidity indoors isn’t good for your health. Instead, what you can do is plant a collection of the same types of plants closer together to increase the humidity just in the grow zone for your plants.
To boost the humidity further, you can use a humidity tray and place layers of lava rock and gravel in it, which hold water for longer and evaporate. As the water evaporates, it will increase the humidity around the plants.
Choose the right type of plant, grow in adequate conditions following the guidance on the label and feed with a nitrogen rich fertilizer and you’ll be able to grow plants indoors fast with ease.
Growing up with a mom who filled her home (inside and out) with all sorts of plants, Lisa got her start in gardening at a young age. Living now on her own with a home and yard full of plants (including an indoor greenhouse), she shares all the gardening tips she’s gained over the years.