Tips for Gardening in Self-Watering Grow Boxes

How to get the most from your grow box

Growing lettuce in wooden box

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Grow boxes solve one of the biggest problems for successfully growing vegetables: giving plants the right amount of water. In conventional container gardening, over-watering, which causes plants to rot, is one of the most common mistakes. Grow boxes are all about controlling the water flow to your plants, making it impossible to over-water and easier not to underwater.

Grow boxes deliver a consistent amount of water to the plants because they work with a reservoir system. You put water into a larger reservoir, and as long as you keep the reservoir full, your plants are getting water through consistently moist soil. To protect your plants from getting too much water, grow boxes come with soil covers. Therefore, even if it rains for days, your plants won't drown. Other grow box tips include:

  1. Fill your grow box where you want it: Even though some boxes come with wheels, they can be tough to move and are heavy once filled with soil and water. Figure out where you want the box to live before you fill it with heavy soil.
  2. Choose a well-protected spot: A grow box that is full of enormous, sprawling tomato plants, though heavy, can blow over in a strong wind.
  3. Follow planting instructions: Do not plant more than the suggested number of plants in your grow box. Although it might seem like you will get more produce if you put in extra plants, your plants will not thrive. The amount of soil and fertilizer has been carefully calculated. Therefore, if you put in too many plants, they will not provide the kind of yields that the right number of plants would have.
  4. Be vigilant about adding water to your grow box: Ignore the advice about the frequency of watering that comes with your box, which almost always overestimates the length of time between having to add water. As your plants grow, their water needs increase—often dramatically—so, by the end of the season, you might have to check the water level every day.
  5. Easy access for watering: Place your box where you can easily add water, preferably where a hose can reach it. The grow box comes with an overflow hole, which is the only way to tell if your reservoir is full. Make sure you can see the hole when water is coming out, so you will know when you can stop watering.
  6. Follow feeding directions carefully: If you don't follow directions and skimp on the advised fertilizer requirements when planting your box, you won't have healthy plants. You may need to add a slow-release fertilizer at the beginning of the season.
  7. Avoid end rot: To prevent blossom end rot, add a cup of dolomite or lime to the top of the potting soil. If your fruit still gets blossom end rot, which you can identify by brown or black rot on the bottom of your vegetables, you can solve this problem by mixing 1/4 cup of lime with 1 gallon of water and adding it to the reservoir. Do this only once.