Container Gardening: Answers to Your Questions

EarthBox container gardening systems growing tomatoes, herbs, and carrots

Retail sales of organic fresh fruits and vegetables have steadily increased for the past two decades (NBJ, 2022). The Organic Trade Association (OTA) reports that organic produce totaled $22 billion. That figure accounts for 15 percent of this country's fruit and vegetable sales.

Unfortunately, organic produce is expensive, sometimes up to 50% more than non-organic grown produce. Moreover, organic fruit and vegetable prices rose 13.1% over the past year. Prices for conventional produce increased by just under 10%, according to Lending Tree.

So, what do you do to enjoy the benefits of organic fruit and produce without the high price tag? Grow it yourself!

Container Gardening Continues Its Growth

Welcome to the increasingly popular world of container gardening. You can grow your produce and know exactly how you grew it. So you can ensure it's organic.

Best of all, container gardening requires little space. You can grow tomatoes, carrots, lettuce, peppers, and much more with a balcony and sunshine. You can even take it inside during winter for year-round fresh produce.

If you aren't familiar with container gardening, here's a little help. EarthBox has been a go-to source for container gardening enthusiasts. So we get all kinds of questions.

We'll answer the most common questions people ask us. If you have others, drop us a line.

What is container gardening?

Container gardening is growing plants in gardening containers rather than in a garden bed. Those containers include garden boxes, pots, planting bags, etc.

You can select from numerous materials, including wooden planters, terra cotta, and plastic pots.

Container gardening opens the world to growing produce for virtually anyone, city and rural dwellers alike.

What is the benefit of container gardening?

Container gardening guarantees that you grow what you plant organically. It gives you control over the soil and amendments. It also allows you to plant with limited space.

You can grow vegetables on a balcony or railing. To conserve space, you can even plant a vertical garden on a patio wall.

You can also use different plant pots to fit your space and add color to an otherwise drab area. Ensure the space offers full sun. Most vegetables require six hours of sunlight.

What can you grow in container gardens?

You name it. You can cultivate a wide variety of plants in containers. You can grow herbs, tomatoes, squash, zucchini, eggplant, strawberries, watermelon, and potatoes.

Use gardening containers for jalapenos, habaneros, cilantro, and oregano if you like Mexican food. Or complement your love of Italian cuisine with basil, Roma tomatoes, parsley, thyme, and sage.

What are the most common mistakes in container gardening?

Common mistakes include:

  • Too much or too little water
  • Underfeeding
  • Using the wrong container size
  • Using poor soil
  • Neglecting drainage
  • Infrequent soil replacement
  • Combining plants with different requirements
  • Overplanting containers

Read more about container gardening mistakes and how to avoid them.

What vegetables grow well together in containers?

Companion planting helps get the most out of container gardening. Try to combine plants that have the same growth rate. They should also have similar sunlight requirements, watering needs, root systems, and maturity height. For example, tomatoes pair well with eggplants, peppers, and basil.

How deep should the gardening container be for vegetables?

The container or planting box can be as little as 6 to 8 inches for shallow-rooted vegetables like turnips. A container with a minimum depth of 12 inches is suitable for deeper-rooted produce. Eggplants, kale, strawberries, and radishes each work well with that depth gardening container.

You must leave a few inches on the sides and six inches of depth for plant growth. Get more insights into container depth here.

What size container is best for tomatoes?

Tomatoes require relatively large containers. Look for a gardening container with a minimum depth of 10-12 inches. It should also be at least 18 inches long for healthy tomato growth.

EarthBox, for example, offers a tomato-growing kit. It includes a tomato planter, soil, fertilizer, trellis, and mulch cover. All you have to do is buy the tomato plants to grow tomatoes successfully.

Get some tips on how to grow tomatoes in gardening containers.

How deep should the container be for herbs?

A more shallow gardening container works for herbs. They typically have shallow roots, so a smaller pot with a 6 to 8-inch depth is usually enough.

Learn more about how to grow herbs in containers.

What's the best material for gardening containers?

Common container materials include plastic, ceramic, terra cotta pots, and wood. Choose based on your preferences and your plants' specific needs.

Every gardening container has its pros and cons. For example, some containers like terracotta are porous, so you'll have to water them more often. Black plastic absorbs heat so that it can burn your plant roots.

Learn more about planting box selection.

How often do you need to water your containers?

Watering frequency depends on plant type, container size, and weather. For example, smaller containers require more frequent watering. Porous pots like terracotta also demand more attention.

Check soil moisture regularly and water when the top inch is dry. In hot summer months, you may need to water twice a day.

What's the best way to water your container?

Always water the soil at the base of plants. Avoid overhead watering that gets plant leaves wet to prevent fungal issues. Use a watering can or drip irrigation for precise watering.

You must moisten the entire root zone. That means watering until it comes out of the drainage holes in the container's bottom.

What is a self-watering container?

A self-watering container is a planter with a built-in water reservoir and wicking system. It provides continuous moisture to plant roots through capillary action.

Self-watering planters eliminate concerns about watering your plants too much or too little.

It also reduces the time watering. After you fill the reservoir, you can generally wait a few days before watering again.

Is a SIP planter the same as a self-watering planter?

Yes, SIP (Sub-Irrigated Planter) and self-watering planters are identical. Their reservoir allows plants to draw water as needed. That reduces the risk of over- or underwatering.

Do you need drainage holes in gardening containers?

Absolutely. Gardening containers must have drainage holes to prevent water from pooling at the bottom, which can lead to root rot. Proper drainage is crucial for plant health. If your container doesn't have holes, drill holes in the bottom to allow excess water to drain.

What soil is best for gardening containers?

Avoid using garden soil. It can compact in a container, creating drainage and aeration issues. Moreover, it can contain insects, weeds, and diseases.

Use high-quality potting soil or light container mix for good aeration and drainage. The soil should also be rich in organic matter. So, add composted manure, worm castings, peat moss, and other organic materials.

Keep the soil pH slightly acidic at 6.5. Most plants thrive in the 6.0 to 7.0 (slightly acidic to neutral) range.

Learn more about how to choose the best potting mix for your containers.

How often should you replace the potting mix in containers?

Typically, experts recommend 12 to 18 months for regular containers. If you use our EarthBox container gardening system, we recommend reusing the same growing media for up to 8-10 growing seasons. Either way, you must replenish the nutrients to reuse the soil.

You can do that by mixing some new potting mix with the old. When you plant your vegetables, include a good fertilizer mix.

How often do you need to fertilize container plants?

Container plants benefit from regular fertilization. For instance, tomato plants are hungry feeders. So, apply a balanced, water-soluble fertilizer every 2-4 weeks during the growing season. Or simply use our pre-measured soil amendments that last the full season.

What is slow-release fertilizer?

Slow-release fertilizers release nutrients gradually over time. They provide a consistent nutrient source for your plants. They reduce the need for frequent fertilization.

Are transplants or seeds better for container gardening?

Both transplants and seeds work for container gardening. Seeds offer a cost advantage. For instance, seed packs cost a couple of dollars versus transplants that run three or four times as much.

Transplants, however, give you a better headstart. Seeds require more growing time, so it's best to use transplants for larger plants like tomatoes and peppers.

EarthBox: Container Gardening Experts

Our container gardening solutions have been industry-leading for nearly 30 years. Commercial farmers developed our planting boxes. They've been lab and field-tested to ensure they work.

Our maintenance-free container gardening growing system controls soil conditions and eliminates the guesswork. Best of all, it can double the yields of conventional gardens with less effort.