Vegetable Container Gardening for Beginners

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Growing your own food can bring you both joy and bounty. There's a simple pleasure in biting into a tomato still warm from the sun—picked and eaten on the spot. You can grow just about any vegetable in a container, a practice that can save you lots of money buying produce at the grocery store. However, vegetable container gardening can be a frustrating endeavor if your plants don't thrive and produce. The following tips apply to most vegetables and can help you and your plants get off to a good start.

Providing the Right Light and Temperature

Most vegetables need full sun, meaning at least six hours of direct sunlight each day. But some gardeners might overestimate how much sun an area really gets. For your veggies to thrive, you'll need an accurate assessment. Check the location every 30 minutes throughout the day to confirm how long the sun directly hits the spot where you want to put your vegetable container garden. You can also use a sun calculator to get an accurate assessment.

If you live in a hot climate, you might need to shade your plants during the heat of the afternoon, so they don't overheat. Also, it's best not to use metal or dark-colored containers because they can become very hot and cook your plant's roots.

On the flip side, many vegetables don’t like cold soil. So if you live in a cool climate, avoid putting your containers outside full time until you know the temperature will be reliably warm. For many plants, the soil needs to be at least 60 degrees Fahrenheit. You can use a meat thermometer to find out the temperature of your soil. In addition, always make sure to harden off your plants (gradually acclimate them to the outdoor conditions) before you put them outside permanently.

Watering Your Container Garden

Many vegetable plants, such as tomatoes, need lots of water. However, you don't want to drown your plants. The goal is to keep the soil evenly moist but not soaking wet.

To figure out whether your plants need water, stick your finger down into the soil about an inch. If the soil feels dry, add water; if you're not sure, wait and check later in the day. At the height of summer, you'll probably need to water at least once or sometimes twice a day. This is often the most high-maintenance and critical aspect of vegetable container gardening.

Using Quality Potting Soil

High-quality potting soil is important for vegetables. Don't use soil from your garden because it will compact in the containers and won't drain water properly. Also, one of the reasons to garden in containers is largely to avoid dealing with weeds. But if you use garden soil, you might be importing weeds into your containers.

Furthermore, studies have shown many benefits to growing produce organically, including better taste and a higher percentage of antioxidants and phytochemicals. Organic soil, which has a higher variety of nutrients than regular potting mixes, comes in a variety of pH levels and blends geared toward different crops.

Feeding Your Plants

Plants need nutrition to thrive, and their food is fertilizer. If your soil doesn’t have fertilizer already mixed in, add some several times throughout the growing season. Many gardeners mix organic, granular fertilizer into the containers from top to bottom before planting. Then, every couple of weeks, add diluted liquid fish emulsion or liquid seaweed to give the plants the nutrition they need. Another way to add fertilizer is to make or buy compost.

Creating Optimal Drainage

Drainage is key to keep plants from drowning. Your container should let excess water out of the bottom, so your plants won't sit in overly soggy soil and succumb to root rot. There should be one large hole or several smaller holes located at the base of your container.

You can usually drill holes if the drainage is insufficient, and you can cover a large hole before adding soil with a coffee filter or plastic screening to keep the dirt from coming out the bottom. If your container sits on a hard surface, the hole might plug up. Elevating your container with pot feet or a pot cart will help your plants drain with ease.

Selecting the Perfect Container

Choosing a container can be daunting. You can use almost anything for a garden planter as long as it's big enough, has good drainage, and is made of food-safe material. But keep in mind that the larger your container is, the easier it will be to maintain. The more soil a container can hold, the more moisture it will retain. In general, don’t bother with containers that are smaller than 12 inches across. Bigger really is better when it comes to growing vegetables in containers.

Wooden Containers

Wooden containers look lovely when growing vegetables, and you can typically find optimal-size containers that aren’t too expensive. Or you can make your own wooden planter box.

Self-watering Containers

Growing vegetables in self-watering containers works well, too. They are large, easy to use, and incredibly durable. And they make watering plants a cinch because all you have to do is keep the water reservoir full.

Ceramic Containers

You also can use plastic or glazed ceramic containers. You can even use terra cotta pots, but it's harder to keep your plants moist in them because the clay sucks the water out of the soil. To help solve this problem, you can line a terra cotta pot with plastic, use a plastic pot as a liner, or seal the pot with a stone sealing product.

DIY Containers

For an inexpensive container, use a 5-gallon plastic bucket from the hardware store. Another alternative is to make an unusual container from something you have around your house, such as an old laundry basket or toy bin. As long as it’s big enough and has good drainage, you can really use anything. You can even grow vegetables in straw bales.

Choosing Seeds or Seedlings

You can start your veggies from seed or buy seedlings. There are some significant advantages and disadvantages to each. Planting your own seeds is much less expensive than buying seedlings. Plus, you can organically grow hard-to-find varieties.

However, starting seeds isn't for everyone. They need 12 to 16 hours of light per day and good air circulation to grow up strong. Plus, you absolutely cannot let the seeds dry out, or they're toast. Conversely, if you give them too much water, they’ll keel over dead. To avoid this, you can make a self-watering seed starter.

Vegetables for Container Gardens

When choosing vegetables to plant in containers, look for bush or small varieties (often referred to as dwarf or compact), and ensure that your climate has enough growing days for the required time to mature.

Plants that typically grow well in containers include:

  • Peas: Put tall supports in the container when planting seedlings. Water frequently, and keep them fertilized.
  • Potatoes: Some potatoes need a 120-day growing season, so look for varieties that mature early.
  • Tomatoes: Like peas, tomatoes need a support system. Use a rod or tomato cage to keep your plants upright.
  • Carrots: Use a container that's double the length your variety will grow.
  • Radishes: Containers don't have to be that large for this spring vegetable.
  • Eggplant: When planning which variety to buy, know that many eggplants are fairly sensitive to cool temperatures (lower than 50 degrees Fahrenheit).
  • Summer or zucchini squash and cucumbers: Choose bush varieties rather than the sprawling vine varieties. One plant can fill a 24-inch pot quickly, so don't crowd your seeds or seedlings. A trellis in the pot will supply support for the fruit and allow air to flow around the plant.
  • Leafy greens: Spinach and leaf lettuce are among the many greens that you can snip to eat one day and then snip again a few days later. Keep the cool-season crops in partial shade.
  • Peppers: Try traditional bell peppers, or spice it up with hot peppers that are perfect for homemade salsa.

Plants that don't usually work well in containers include:

  • Large melons
  • Corn
  • Large pumpkins or squash