For the past decades, container gardening has grown to be so popular. Reason; it gives the plant owner the freedom to grow plants in places that are not traditionally ideal for growing. People in rental spaces and those living in high-rise apartments can benefit from container gardening.
Moreover, those who don’t want to tear up their beautiful yards generally opt for growing plants in plant pots. However, the biggest concern is, do bigger pots mean bigger plants?
Bigger pots does not mean bigger plants. The recommended pot size for transplanting is between 2 to 4 inches larger in diameter from the pot that the plant was planted in. This gives the roots enough space to spread and absorb more water and nutrients. Excessively larger Pots will have higher water retention and require more nutrients for plants to grow.
The most significant aspect of planting in potters is choosing the right pot size. Choosing the wrong size can adversely affect the roots and the plant’s ability to absorb nutrients. Therefore, the size of the pot is directly proportional to the plant size. Why? Let us take an in-depth visit to the general facts about the pot’s effects on plant size.
How Can A Bigger Pot Affect Root Production?
The average potted plant is planted in a container that is circular or cylindrical in shape. This means that with an increase in diameter of 4 inches would add two inches all the way around the plant.
For larger pots 10” and greater in diameter, an increase of 2” would be too small and would not provide much substantial spacing for the plant to progress in growth and you would have to transplant again in a shorter period of time.
Depending on other factors considered in root growth. Generally, roots need larger pots to grow and take in many nutrients for the plants. Bigger pots mean more root spaces, significantly when the right quantity of organic nutrients is amended into the soil before planting.
How Smaller Pots Affect Root Growth
First things first, soil serves as the primary source of nutrients for roots and plants. Smaller pots mean less soil in the pots, which reflects fewer nutrients.
Since both the root system and plants depend on the nutrients to grow, smaller pots constrict the root to grow and take in more nutrients. This happens mostly on plants with more significant roots.
Roots growing in smaller pots get packed together and lack spaces to spread out. As a result, fewer nutrients are absorbed, leading to slow plant growth.
Moreover, you may notice your plants tipping over due to heavier plant weight than the supporting roots. Other effects of smaller pots include inadequate water to support the plant, making the soil dry out quickly. This leads to drought signs in plants sooner than expected.
How Too Large Pots Affect Root Growth
Many plant owners would assume that too large pots are the best for the root system. However, the case may not be valid for all plants. Why? An oversized pot gives the roots more room to spread out but can also have adverse effects on the root system.
This is because too large a pot holds a lot of water, which takes too long to dry out. Excess water in the soil can lead to mold growth, root diseases, and rotting.
Too large pots also make it difficult for roots to pack together and hold the soil firmly around them. A scattered root system leads to improper nutrients intake, leading to slow root production and plant growth.
Therefore, plants growing in a too-large pot can look out of proportion with the container as a result of growth problems.
Moderate Pot Size and Root Growth
What is the ideal pot size for the best root production? The right pot size entirely depends on the type of plant, its size, and the needs. The right pot size should allow effective root system spreading and good drainage.
When repotting the recommended pot size is between 2 to 4 inches larger in diameter from the pot that the plant was planted in. This gives the roots enough space to spread and absorb more water and nutrients which results in larger, more healthy plants.
Therefore, the best pot should not be soaked after watering and should allow water to drain out from the bottom.
This means plants in a too-small container (eg. 2”in diameter) should be transferred into a pot that’s about 4 inches in diameter. You can also go for the higher end of the range if your plants tend to grow quickly.
Mostly, the containers from the nursery are not of the right size. For instance, a tomato container size from the nursery is usually smaller than the recommended pot size.
This is usually done when planting commercially to save on space.
Therefore, do not use this pot when evaluating the right size for tomato containers Or any other pot bought from the plant shop.
Nursery containers are not designed to hold the plant for long-term use. They are only meant to sustain the plants until they are transferred into the appropriate pot or ground.
Can Having A Bigger Pot Grow Bigger Plants?
From the basics, bigger pots mean a vast root system that takes in more nutrients for plants. Therefore, generally, bigger pots result in bigger plants due to adequate nutrients and water. However, there are several exceptions to this rule.
Plant growth is determined by factors other than the soil content and the nutrients needed. These factors include temperature, light, and air.
Assuming the plants get the right temperature, light, and air circulation, we focus on the plants’ nutrients. While some people apply liquid fertilizers added in water, others only apply solid fertilizers and water the plants.
Whatever the method you use, plants will grow bigger and stronger provided they get the right nutrients and water. Roots only grow bigger to reach nutrients.
Therefore, a more extensive root system is not needed if the plant is provided with everything directly through watering. So, how do the soil content and the pot size affect the size of the plant?
Taking an example of the fiddle leaf fig plant, providing it with enough nutrients during watering sessions means a smaller pot can be efficient.
Another factor to consider when evaluating the pot size is the ‘root bound’ or ‘pot bound’. This is when the roots grow faster and reach the walls inside the pot. In smaller pots, roots quickly reach the walls of the pot and are wrapped inside the pot.
This leads to root tangling, which blocks the nutrient uptake. As a result, there is slow plant growth, leading to smaller plants.
Therefore, to prevent this, gardeners are encouraged to use bigger or root pruning pots. However, using too large pots leads to root overspreading, neglecting the nutrients in the center of the pot.
Does More Roots Mean More Nutrient Uptake by Plants?
Roots account for a larger percentage of nutrients uptake by plants under natural and cultivated conditions.
However, foliar uptake is vital under other circumstances, especially in densely populated areas where plants need significant amounts of Nitrogen and other nutrients.
Nutrients get to the plants in two ways:
- Foliar sprays are also applicable in nurseries and forest plantations to correct micronutrient deficiencies. Therefore, can the size of the root system affect nutrient uptake?
- Roots take in nutrients in the form of inorganic ions from the soil solution. The uptake rate depends primarily on the nutrient solution concentration adjacent to the root surface.
Therefore, plants get nutrients either by roots growing towards the nutrients or the nutrients getting to the plant via its leaves.
The nutrients uptake by the plants depends on several factors, including;
- Soil Structure
Soil structure affects how the nutrients reach the plants. For instance, compacted soil limits the ability of the root to spread to reach the nutrients.
It also limits water to move towards the roots and get nutrients for the plants. Therefore, dense soil restricts root growth, even when the plants have more roots.
This is the opposite for loose soils where water and nutrients can get easily leached out of the soil and into the plant pot.
If you have pets around, you may want to ensure that the plant saucer is not accumulating unused water and nutrients which can affect pets if they happen to drink the water.
See our detailed article on how plant drainage water can affect pets.
- Nutrient Concentration
The level of nutrient concentration in the soil impacts how the nutrients move in the root system. For instance, a higher concentration means a higher amount of nutrients will be available for the plants during nutrient intake.
This is why a plant owner should ensure the soil has a higher nutrient concentration for the potted plants. Care should be taken where application of fertilizer is concerned.
Adding too much fertilizer can also be harmful to plants whereby the nutrients can be so concentrated in the soil that it causes burns to the plant and can even kill the plant in extreme circumstances.
- Nutrients Mobility
The speed at which the nutrients move towards the root determines the plants’ rate of nutrients uptake. Different nutrients have different mobility.
The nutrient mobility if affected by how well it is absorbed into the water in the soil. Nutrients when absorbed by water breaks up into positively and negatively charged ions.
These ions move with the water particles into the root system and to various parts of the plant where it is needed to carry out the plant’s biological functions.
- Nutrient Absorption
The connection between the nutrients impacts how quickly they are absorbed. If they are firmly connected, it will be harder for them to break and move towards the roots.
This again, is where water comes in. If there is not enough water in the soil to break up the nutrients so that it can be available for the roots, then the plants will not get the nutrients that are being supplied for them to grow.
Nutrients are absorbed when the concentration of nutrients is higher in the soil than in the root structure by a process called osmosis.
Osmosis is the spontaneous net movement of solvent molecules through a selectively permeable membrane into a region of higher solute concentration, in the direction that tends to equalize the solute concentrations on the two sides.
As a result, a higher nutrient concentration in the soil than the roots will cause the nutrients to be absorbed into the roots and then the plants.
When to Repot A Plant? (Signs A Plant Shows When They Need Repotting)
Potted plants do not stay little for long, and you need to change the pot after some time. For some reason, you may notice your plants looking a bit out of place in the potter that they are planted in..
This happens even when you provide them with the right light exposure, fertilizer, and the right watering session. However, do not worry because these are simple signs that your plants need repotting. Additionally, here are signs to show your plants need repotting;
- Poor Soil condition (looks poor)
Soil watering is vital for the plants, even if you understand your plants’ specific needs. For example, indoor humidity plays a vital role in soil quality and varies from home to home.
Once you realize your soil needs routine watering to keep its temperature and moisture relatively consistent, it is time to change the pot. This also shows your plants are growing, and their thirst is increasing, which depletes the soil nutrients.
- Roots showing on topsoil and through drainage holes
A faster-growing root system will outgrow the pot. You will notice roots growing over the pot and through the drainage holes.
Once you notice the pot cannot accommodate the faster-growing root system, it is time to transfer the plant into a new larger pot.
- Water Absorption
Repotting does not only mean getting a bigger pot. Some plants also need to be transferred into a smaller pot for various reasons. For example, yellowing leaves means the plants are getting too many nutrients or water.
For this case, you should repot them to smaller pots to limit the amount of water absorbed. This also restricts the root system from absorbing excess nutrients, which moderates the plant growth.
- The pot looks too small.
The size of the pot is the primary factor considered when repotting. Plants grown in too small pots will generally have a heavier half top.
This can lead to tipping over, and a gardener should consider repotting to a wider planter. Additionally, some plants tend to grow wider than taller and need wider pots to remain healthy.
How to Repot A Plant?
Now that you have noticed some signs your plant needs repotting, how do you do it? Mostly, repotting means changing the plants to the new pot with suitable conditions.
This involves choosing the right container that is at least 3 inches wider than the original pot. You also need to select the right potting mix, created explicitly for indoor gardening like Good Dirt. Therefore, here are the steps on how to repot a plant;
- Removing the plant from the current pot
Start by watering the plant an hour before repotting to make it easier for removal. Hold the plant gently by the stem and tap the bottom of the pot until the plant slides out. You can also gently tug on the base of the stem to remove the plant quickly.
- Loosen the roots
Use your hands to loosen the roots gently. You can also prune off any threadlike and extra-long roots. Ensure you leave the thicker roots at the base of the foliage. If your plant is root-bound, unbind the roots and trim them.
- Adding new potting mix to the new container
Add fresh potting mix to the new pot, pack it down, and remove any air pocket. Layer the bottom with lava rocks or gravel if the pot does not have drainage holes before adding the potting mix. This gives more crevices for more water to get in.
- Adding the plant
Set your plant at the center of the new pot and the top of the potting mix. Add more potting mix around the plant to secure it. Do not put excess soil in the pot to allow more breathing spaces for the roots. Do not forget to water your plants in the new pot.
Types of Plant Potters
Potters are made from different materials. Some will best suit your specific plants, while others will not. For the plant to grow effectively in any potter, it should have enough space and drainage holes in the bottom. Moreover, keep in mind that a plant needs a premium quality potting mix for its growth. Here are some of the common potter types used by gardeners;
- Clay pots are readily available but very expensive and more decadent. Clay pots are also easily breakable when dropped and subject to cracking in cold temperatures.
- Plastic pots are versatile, lightweight, durable, and affordable. Some plastic pots are more attractive than others and have realistic finishes. Another advantage of plastic pots is that they do not need frequent watering like clay pots.
- Glaze Ceramic pots are the most colorful, ranging from playful, vibrant glazes to subtle earthy tones. Most glazed ceramic pots are less subject to a freezing condition, thus more durable. However, they are relatively expensive and more solemn, since most are imported from Asia.
- Fiberglass pots are classically designed, durable, and lightweight potters that attract premium prices. Due to their high price and quality, fiberglass pots are harder to find in the market, and you have fewer choices to pick.
Having the right pot size for your plants can bring multiple benefits for your plant and your living space. Choosing a larger pot to repot a plant is obvious but choosing an oversized pot can also have negative effects on a plant’s development.
There is a lot to be said about why you should always choose the right pot size for your plants, but it all comes back to how you care for your plants. To get the best root system and plant growth, ensure that the pot is of the right size.
You should also provide the plants with the required nutrients, water, and air quality. Lastly, pay attention to the pests like aphids and mites, and check for repotting signs.