How Big Should Your Plant Pots be for Container Gardening?

Container gardening is a fantastic way to bring fresh, vibrant plants into your home, regardless of your available space or outdoor area. This way, not having enough backyard or lawn space is not a reason not to grow a lovely garden.

One of the most important aspects of container gardening is choosing the right size of pots for your plants. The size of the pot will directly affect the growth and health of your plants, as well as their overall aesthetic appeal.

In this article, we will explore the key factors to consider when selecting the size of plant pots for container gardening, including the types of plants you want to grow, the space you have available, and your personal preferences. Whether you are a seasoned gardener or a beginner looking to start a container garden, this article will provide you with valuable insights into choosing the right size of pots for your plants.

Why Does Pot Size Matter?

Just like an Englishman’s home is his castle, a plant’s pot can be considered as its palace – a safe haven, a personal space to grow, and a place to flourish. Choosing the right pot for your plant is essential, and it’s not a decision to be taken lightly. Matching your plant to its pot is a decision that requires thoughtful consideration if you want to successfully take care of your plants and reap a harvest out of them.

For vegetables and herbs to mature properly when grown on patios, balconies, and rooftops – the pots and containers used must be of sufficient size. These containers must provide ample space for both the soil and moisture, providing the necessary nutrients for the plants to leaf, flower, and fruit. It’s essential to choose a container size that is large enough to accommodate the plant’s roots and prevent the pot from tipping over due to the height and weight of the above-ground growth.

What Happens if the Planters Are Too Big?

Studies have shown that increasing the pot size of certain plants can result in a growth increase of up to 40%. However, it’s crucial for any plant to maintain proper water levels, provide sufficient nutrients, and use the appropriate soil mixture to ensure optimal health. Here are the cons of using a planter that’s too big:

1. Plants may struggle to establish a healthy root system in a too large container. The excess soil can hold too much water, causing the roots to stay damp and increasing the risk of root rot. As a result, the plant may not be able to take up enough nutrients, which can affect its overall growth and health.

2. A planter that is too big can make it challenging to maintain the correct moisture levels in the soil. The larger volume of soil can dry out more slowly, leading to overwatering, which can also harm the plant’s roots. When too little water is used, the large volume of soil will be too dry.

3. A planter that is too large can also cause aesthetic problems. The plant may look lost in a large container, and the excess soil can make it difficult to create an attractive display. From a proportionality perspective, it may look off.

What Happens if the Planters Are Too Small?

A too-small planter can also cause problems for the plants, such as the following:

1. The restricted space can cause the plant’s roots to become root-bound, meaning they have outgrown the container and begin to grow in circles around themselves. This can cause poor nutrient absorption, stunted growth, and overall poor plant health.

2. A small planter can cause moisture retention problems. The limited volume of soil in the container can quickly dry out, leading to dehydration and stress in the plant. On the other hand, if the soil is overwatered, there may not be enough room for proper drainage, leading to root rot and other issues.

3. A small container may not provide sufficient space for the above-ground growth of the plant, leading to overcrowding and a lack of airflow. And when it happens, the plants are susceptible to diseases and pests, which may also impact their overall appearance.

Tips for Choosing the Right Pot Size for Your Plants


Knowing what size of container to use is a crucial part of gardening in containers. Unlike traditional gardening on a soil bed, you have more things to consider when planting in containers. Here are some general tips to help you:

Consider the size of the plant

Choose a pot that is appropriate for the size of your plant. If the pot is too small, the plant may become root-bound, while a pot that is too big may lead to drainage and moisture retention issues. Later on, we will discuss what types of plants are appropriate to plant in different sizes of containers.

Consider the roots

The size of a plant’s pot is more about what’s happening \beneath the soil than above it. While different plant varieties have varying requirements for pot size and root development space, most plants tend to thrive when their pot size is at least two inches larger in diameter than the plant itself. This provides sufficient space for growth as the plant matures and establishes itself.

Know how pots are measured

To make sure you got the right size, you need to know how to measure your pots as they come in different shapes.

Plant pots are typically measured by their diameter, which is the distance across the broadest part of the pot opening. For round pots, this measurement is taken across the top of the pot, while for square or rectangular pots, it’s taken across the diagonal. Pot size is typically expressed in inches or centimeters, depending on the country and the manufacturer. For example, a pot labeled as “10-inch diameter” means that the opening at the top of the pot is 10 inches across.

In addition to the diameter, the height of the pot is also an essential factor in determining the overall size and suitability for a particular plant. Therefore, some pots may also be labeled with both the diameter and height, such as “10-inch diameter by 8-inch height.”

Also, there are pots measured in trade gallons, which refers to the volume of soil it can hold.

Consider the space you have available

Think about the location where you plan to keep your plants. Is it a big or small space? Smaller pots that fit on a windowsill or table may be the best choice if you’re growing plants indoors. These pots save space and make it easier to move your plants around and provide the necessary sunlight they need.

On the other hand, if you have a larger outdoor space, you may want to consider larger pots that can hold more soil and accommodate bigger plants. Larger pots offer more stability and can withstand harsh weather conditions better than smaller ones. Keep in mind that larger pots can be heavy, so be sure to place them in a location where they will be moved only occasionally.

Another option to consider is grouping smaller pots together to create a cluster of plants. This can be a great way to maximize your space while also creating a visually appealing display. You can choose pots of varying sizes and colors to add interest and variety to your collection of plants.

Think about the plant’s growth habits

Consider the growth habits of your plant when choosing a pot size. For example, plants that grow tall and narrow may need a pot with a smaller diameter but a greater height. This allows the plant to grow upward while still having enough room for root development. A tall, narrow pot can also help support the plant as it grows and prevent it from toppling over.

On the other hand, plants with a spreading habit, such as ferns, may require a pot with a larger diameter to allow the roots to spread out and support the foliage. A wider pot can also help prevent the plant from becoming too top-heavy and tipping over.

Check the drainage holes

When it comes to potted plants, proper drainage is crucial. Opting for a container with holes at the bottom is always the best choice, as it allows you to adjust the watering needs of each individual plant. Using a container without a drainage hole is generally not recommended unless you’re well-versed in the plant’s water requirements.

Ensure that the pot has adequate drainage holes to prevent water from pooling in the soil and causing root rot. Place a saucer underneath the planter to catch any water that leaks out, preventing it from pooling and causing waterlogging.

Check the thickness of the pot

Thicker containers can protect plants against extreme outdoor temperatures, from frost to heatwaves. The added insulation of thick planters can also help reduce the impact of rapid temperature changes, which can harm the plant’s health.

Be aware of the consequences of overpotting

Choosing a pot that is too large for your plant, also known as overpotting, can lead to problems with aeration and moisture levels within the pot. Larger containers tend to retain moisture for longer periods, which can cause issues such as root rot, yellowing leaves, and even plant death. In such cases, downsizing to a smaller, appropriately-sized pot can help combat these issues.

While sizing up is a more common approach to choosing a pot size, there may be situations where a smaller pot is needed. It’s important to consider the potential risks of overpotting and ensure that your plant has enough room to grow without being drowned by excess moisture. By carefully selecting a pot size that provides the right amount of space and ventilation for your plant, you can help ensure its health and vitality.

Know when to size up

As a gardener, you need to know the signs indicating that your plants need to be repotted. Almost all plants will require repotting at some point in their life cycle. You may notice that plants require watering more frequently when it’s time for a report. Another telltale sign is if you see roots emerging from the drainage holes in your current pot, indicating that it’s time to switch to a larger container.

The frequency of repotting will depend on various factors, such as the plant species, growth rate, and size. Most plants will require a new container every two years.

Guide to Plant Pot Sizes

Check out this guide to container sizes. But before that, here are some things you should take note of:

  • Plant pot sizes are not standardized, and they may use different types of measurements.
  • The sizes listed here are measured by the amount of soil they hold.
  • It’s always best to choose the largest possible container when growing vegetables to give them proper access to soil, food, and water.
  • Aim for the container to be as deep as it is wide to provide the most room for the roots.
  • Extra small containers that hold less than two gallons of soil are not recommended for growing vegetables to maturity. You may need to replant them on a larger pot as they grow.

Extra Small Containers


It can hold up to two gallons of soil

Examples: 8″ nursery pot or terra cotta pot, 10″ hanging basket, 2-gallon grow bag

Plants that grow well in extra small containers:

  • Arugula
  • Basil
  • Calendula
  • Chard
  • Green onions
  • Kale
  • Lettuce
  • Nasturtium
  • Rosemary
  • Sage
  • Thyme

Small Containers


It can hold up to three gallons of soil

Examples: 10″ nursery pot or terra cotta pot, 14″ hanging basket, 3-gallon grow bag

Plants that grow well in small containers:

  • Beets
  • Carrots
  • Celery
  • Cilantro
  • Dill
  • Kohlrabi
  • Leaf lettuce
  • Marigold
  • Strawberries
  • Turnips
  • Zinnias

Medium Containers


It can hold up to five gallons of soil

Examples: 12″ nursery pot or terra cotta pot, five-gallon plastic bucket, five-gallon grow bag

Plants that grow well in medium containers:

  • Beans
  • Cabbage
  • Cucumbers
  • Ginger
  • Lemongrass
  • Okra
  • Peas
  • Peppers
  • Potatoes
  • Spinach
  • Turmeric

Large Containers


Can hold up to ten gallons of soil

Examples: 16″ nursery pot or terra cotta pot, 10-gallon fabric grow bag

Plants that grow well in large containers:

  • Broccoli
  • Cauliflower
  • Eggplant
  • Zucchini
  • Sweet potatoes
  • Tomatoes

Extra Large Containers


Can hold up to 20 gallons or more of soil

Examples: 18″ terra cotta pots, 24″ terra cotta pots, 20-gallon grow bags, half wine barrels

Plants that grow well in extra-large containers:

  • Apple trees
  • Dwarf citrus trees
  • Fig trees
  • Peach trees
  • Pomegranate trees