Watering plants in fabric pots is different than watering plants in traditional containers. Learn about the best ways to care for your plants below.

watering plants in fabric bags
Automating watering plants in fabric bags


Introduction to fabric bags

Fabric grow bags are unlike traditional types of pots like terra-cotta, plastic, etc. Grow bags are a fantastic choice because they create the perfect environment for healthy roots to thrive. Additionally, they don’t experience some of the same problems that traditional containers experience. Traditional container materials have problems with the root zone including:

  • root-bound plants
  • root rot
  • slow drainage

These common container problems are not an issue for fabric grow bags because the fabric is a semi-permeable membrane which allows for oxygen to freely enter the root zone unimpeded. Plants need oxygen for respiration. It’s critical to their health and development. This is one of the big reasons plants grown in fabric bags tend to outperform plants in plastic containers.

Grow bags

Grow bags come in all kinds of shapes and sizes. Click here to see different variations of MEG’s grow bags. The larger bags (over 1 gallon) have caring handles making them easy to move. This is especially handy when we have late frosts in Minnesota. The bags can be moved inside overnight. If the bags look familiar, it’s because they’re made of heavy duty landscaping fabric. These bags should last seven years or more, and they can even be machine washed. Grow bags also store well and can be easily folded for storage over winter.

All about water

Plants need water. It’s something everybody knows, but there are specific things to know about the type of water that is being applied to your plants.

City water

Every city’s water will be different due to the source of the water and how it’s treated. Federal, state, and local ordinances dictate how the water must be treated, but there will still be variances from city to city. The EPA’s requirements for city water pH is 6.5-8.5. This may not seem like a big deal, but if your city water supply is sitting around 8 for a pH level, your plants will not thrive. They will most likely suffer. pH is a measurement of hydrogen in the water. The lower the pH, the more hydrogen is available in the water. Plants need a pH level at neutral (pH of 7) or slightly acidic to thrive. This is because many of the chemical elements a plant needs for building blocks require hydrogen in order to be absorbed into the roots of the plant. Science is fun!!!

How to check the pH level of your water

Checking the pH level of your water is easier than you may think. If you live in a city, there’s most likely a public report that has been released for viewing.

If you’d like to perform your own test, there are low-cost methods. Visit your local pet store and pickup an aquarium water testing kit. You can usually get an aquarium pH test kit for $5-10. These typically have a bottle of reagent with a test tube. This type of setup will last you years. Another low-cost method is using pH test strips. These can be found at a pet store also. They are dip strips you place in the water being tested. The strip will turn a particular color corresponding to the stated pH level on the decoder ring.

Soft water

Hard water is a big problem in the Midwest. Most homes have water softeners in order to combat this problem. However, this is the last type of water you should give your plants. Water softeners uses an ion exchange where Magnesium (Mg2+ ) and Calcium (Ca2+) ions are exchanged with Sodium (Na+) ions. Sodium is not an essential chemical element for plants. In fact, it will cause BIG problems for your plants if too much of it accumulates in the potting soil. What to do? Use water from your hard water supply when watering your plants in fabric pots. The plants will actually appreciate the added calcium and magnesium from the “hard water”.

How plants use water

Plants need water just like we need water. Fruiting plants especially need water because much of the fruit’s weight is water weight. In order to create this delicious fruit (think juicy tomatoes and watermelon), the plant needs water to pull nutrients out of the soil. If you think of the plant as a Lego sculpture, then the building blocks are equivalent to the mineral nutrients in the soil. There are three basic ways these nutrients can get to a plant’s roots.

  • Mass flow
  • Root interception
  • Diffusion

Let’s briefly discuss the big one here. That is mass flow. Mass flow, in its simplest definition, means the process of water moving nutrients to the roots to be absorbed by the plant. The majority of the nutrient building blocks for the plant will arrive to the roots via mass flow which means water needs to be present in the soil … which means water has to be applied on a consistent basis! This is especially true for grow bags.

6 Best practices for watering plants in fabric pots

Here’s a list of some of the best practices for watering plants in fabric pots:

  • Check the grow bag for moisture: stick your finger in the soil. If soil sticks to your finger, the plants has enough water. If not, the plant needs water.
  • Use water that hasn’t been softened
  • Water thoroughly and often
  • Avoid splashing water onto the leaves of the plant (i.e. peppers or tomatoes)
  • Apply water to grow bags until water seeps out of the bottom of the grow bag
  • Larger plants with larger leaves will need more water. Plants like cucumbers may need to be watered twice a day during the hotter days in summer.

Plants that chug water

Bigger plants or plants with larger leaf area will require more water. Additionally, plants which produce fruit add to this water requirement. Keep in mind, as the plant grows and enters its fruiting stage, it will require more water than it did when it was in the vegetative growth stage. Your plant may require watering more than once during a hot day. Here’s a list of plants requiring a lot of water:

  • Pumpkin
  • Cucumber
  • Zucchini
  • Watermelon
  • Larger tomatoes (i.e. slicer or beefsteaks)

Plants that sip water

Non-fruiting plants and smaller plants like flowers and herbs will require less water. Some of these types of plants can go a couple days without water, but it’s best to keep an eye on your plants daily when the summer months arrive. Here’s a list of water-sipping plants:

  • Herbs
  • Flowers with small leaf area (i.e. violas, cornflowers)
  • Root crops (i.e. garlic)

Watering during the different seasons

Watering plants in fabric pots will be different depending on the season. In Minnesota, we tend to have frost overnights in the early spring with daytime highs in the 40s and 50s. Early-season plants like leafy greens will be in their early vegetative stages, and won’t require daily watering. As the season transitions from spring to summer, the watering requirements will increase. Most plants have an exponential growth pattern they follow before they get to their flowering and fruiting stages. The water requirements will increase at the same rate. Expect to add water daily once summer arrives all the way up to fall. Watering can be automated. As fall progresses, the pattern will look similar to spring time with less water being required except for vegetative leafy plants. They will still require more water than say a pepper plant which has a ripening fruit load.

I’m going on vacation, how do I water my plants?

Watering your plants can be automated. This is helpful when you go on vacation or you’re out of town for the weekend. Regardless of where you’re at, your plants still require water to grow and thrive. Here are a few ideas to help you have a stress-free vacation:

  • Hire a neighbor kid to water your plants
  • Place your grow bag (s) in a tub or water
  • Use an automated irrigation timer
  • Use a gravity fed or wicking system

Final Thoughts

No matter what type of edible plant you have, it will need water. Make sure to water frequently and water thoroughly. Your plants will thank you!