GrowBox review Reviews

GrowBox Review

GrowBox review

GrowBox self watering planters from Garden Patch have been around for a few years but they’ve recently introduced some new colors, including this fun eggplant color. So I thought it was time to try it out and see how it would work for growing greens in the harsh, sunny climate of Tucson.

Assembling the GrowBox

assembling the GrowBox

The planter (left) snaps onto the water reservoir (right). Note the pins and flaps in the bottom of the planter – those need to be separated from the surrounding plastic.

The GrowBox arrives in two pieces that you have to fit together, including the 4-gallon water reservoir and the planter, as well as a Nutrient Patch cover. Everything you need to grow plants comes packaged in one box, except for the growing medium (potting mix) and plants or seeds. The box also includes a sheet of very detailed assembly and planting instructions, complete with photos.

No tools are required to put the GrowBox together but you may want to have some sturdy scissors on hand to separate some of the plastic parts.

Be Careful and Go Slowly When Assembling

I found it difficult to remove the four pins (meant to secure the cover into the growing medium) from the bottom of the planter box to which they were attached. Be careful when you do this as the edges can be very sharp and I ended up cutting my finger on one of the pins.

Soil wicking in GrowBox

The hinged flaps in the bottom of the planter bend down to create a “wick” that you fill with potting mix.

It’s also difficult to bend the two hinged flaps into place in the bottom of the planter. These flaps, when pushed down, create a square hole into which you pack potting mix; this allows water to “wick” from the reservoir into the planter. Go slowly and don’t push too hard on the flaps or you’ll find that they don’t seat properly and you’ll have a hard time pulling them back into place.

The planter box fits easily onto the water reservoir that sits below it. Make sure you align the edges of the planter top and bottom before snapping the top onto the pins on the reservoir.


Once assembled, the planter is just over 12 inches wide, 27 inches long and 11 inches tall. Somehow I expected it to be bigger… but you can still grow an awful lot in that small space.

Filling the GrowBox

GrowBox full of potting mix

Be sure to water the potting mix thoroughly when the GrowBox is only half full. Then fill it all the way to the rim (or even above the edge) and water again.

Follow the instructions carefully to add the growing medium to the GrowBox. To ensure that the growing medium is nice and moist, the instructions ask you to fill the planter only halfway full with potting soil or growing medium, then fill it with water, and then put the rest of the growing medium on top before watering it again.

If there are dry patches or areas in the container, it won’t be able to adequately wick moisture from the reservoir up to the plant roots.

Growing in the GrowBox

The GrowBox is intended for intensive cropping, also called square-foot gardening (see our review of the Garden Stamp for another way to do this). The point is to grow as much as possible in as small a space as possible while minimizing the amount of work required.

To make that happen you need to provide ideal growing conditions to support a lot of plants. So the GrowBox comes with a special blend of fertilizers and nutrients and a cover that inhibits weed growth and retains moisture.

About the Nutrient Patch Cover

Nutrient Patch on GrowBox

There are two fertilizer sleeves attached to the bottom of the Nutrient Patch. The sleeves dissolve on contact with water.

The cover is made from organic woven material and fits inside the top of the GrowBox (on top of the growing medium). Attached to the underside are two sleeves full of low-salt fertilizers and nutrients that are intended to provide just the right combination of elements to support rapid, strong and healthy plant growth. These fertilizer sleeves dissolve on contact with water so keep them dry until you’re ready to start growing.

Two Types of Nutrient Patch

There are two versions of the Nutrient Patch – one with a 9-14-15 blend of synthetic fertilizers (this is the original Nutrient Patch and the one used in this review) and one with an OMRI certified blend of fast-acting organic fertilizers that includes microorganisms that rapidly break down the materials and minerals into nutrients and trace elements that plants can then readily feed on.

cutting out planting holes in GrowBox

The Nutrient Patch cover is easy to cut with household scissors. Be sure to cut holes only as indicated by the instructions.

Replacing the Nutrient Patch

The company recommends that the Nutrient Patch be replaced each time you replant the GrowBox (the Nutrient Patch can be purchased separately online). That’s probably the easiest way to ensure good results but I’m going to reuse the cover as many times as possible to see how long it lasts and will use my own combination of organic and/or synthetic fertilizer and nutrients. I’ll update this review in the future to let you know how that turns out.

Planting the GrowBox

The Nutrient Patch cover is printed with planting instructions and has 18 spots marked on the surface to indicate the locations where plants should be placed. Take a good look at the included instruction sheet because it tells you exactly which spots to plant in depending on what variety of vegetable, herb or flower you’re growing.

GrowBox with Nutrient Patch cover

A GrowBox all ready to plant!

I chose to grow romaine lettuce (a terrific and tasty blend of red and green romaine called Renee’s Caesar Duo from Renee’s Garden Seeds) so followed the instructions to cut out eight holes evenly spaced around the perimeter of the cover.

If you’re growing seeds you cut out a round hole so you can drop the seed(s) onto the growing medium below. If you’re growing plants then you would cut a slit from the edge of the cover to the spot indicated. That way you can slide the stem of the plant through the slit and dig the roots into the grow medium.

Plastic Pins Need Improvement

Once everything is in place, you’re supposed to use the plastic pins to fasten the cover to the growing medium below. I found that they didn’t stay in place. Any breeze got under the edges of the Nutrient Patch and blew it off the GrowBox. I ended up using a couple of stones to weight it down but landscape staples would probably have worked too. The pins just aren’t long enough to hold down the cover.

After two months in the GrowBox, the lettuce were ready to harvest. Big, strong, and tasty.

Watering the GrowBox

harvest of lettuce in GrowBox

A bountiful harvest of romaine lettuce. Note the salt or mineral build-up between the planter and water reservoir.

Watering is easy. Just keep the water reservoir full (don’t water from the top). You don’t need to keep it topped up but don’t let it dry out completely. I tried filling it with a watering can, hose, and by placing the end of a drip irrigation line into the reservoir. All methods worked well.

One thing I noticed was an unsightly build-up of salts between the planter and the reservoir. That could be partially due to the high mineral content in our water here in Tucson, but also seemed to be from the fertilizer. It was difficult to remove, even with scrubbing.

Supporting Taller Plants

It you’re growing larger plants, like tomatoes, the company offers a support cage for $24.95. I used it for growing tomatoes and found that it worked adequately. However, it took a lot of adjusting to assemble, the plastic zip ties that held it together got brittle and broke after a few months, and the shock cord inside the supports snapped when I disassembled the cage at the end of the season. I don’t recommend buying the support cage, although you’ll definitely need some kind of support when growing tomatoes and the planter isn’t deep enough to be able to stick a tomato cage or support into the potting mix.


4-shovel rating from GPRThe GrowBox makes it easy to grow vegetables and flowers in a small space. It’s relatively simple to put together (if you do it carefully), small enough to move when needed, and works as promised. The Nutrient Patch takes the guess-work out of feeding your plants as they grow. I’d have liked to see sturdier and longer pins to hold the cover down but overall give it a four-shovel rating.

Update May 2016: The GrowBox is still working well. The color doesn’t appear to have faded and the tomatoes growing in it are doing well. I didn’t use a Nutrient Patch this year but did add significant amounts of organic tomato fertilizer. And I built my own support cage using bamboo stakes in the corners and twine strung between the stakes – it seems to be working well and was a lot easier to set up than the Garden Patch support system.

Where to Buy

The GrowBox is available directly from Garden Patch for $29.95 ($8 more for the designer colors, like the eggplant reviewed here), plus $6.95 S&H. A replacement Nutrient Patch is $8.95, or $13.95 for the organic version.

The GrowBox is also available on Amazon, as is the nutrient patch, but they cost slightly more.

And now over to you – Have you tried a self-watering outdoor planter for veggies? How did it work? Let us know in the comments below!

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Disclaimer – GPReview would like to thank Garden Patch for giving us a free GrowBox to review and Renee’s Garden Seeds for providing the lettuce seeds. There was no expectation that it would be a positive review and we received no compensation for writing it. All opinions expressed here are those of the author based on personal experience using the product.

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Disclaimer – GPReview would like to thank the manufacturer/distributor for giving us a free sample to review. There was no expectation that it would be a positive review and we received no compensation for writing it. All opinions expressed here are those of the author based on personal experience using the product.

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22 Comments on GrowBox Review

  1. Just rec’d our order of 6 The Garden Patch GROWBOX containers and was courious about the Vegetable PLUS+Fertilizer 9-14-15. Did you use this type all the time in your grow boxes? Was researching where to purchase some local for future use, but seems only Garden Patch has this specific formula because of salt content. Any suggestions? We’ve always gardened inground, but age is working its toll so trying out this new way. Maybe this is just a perk to only buy with Garden Patch!

    • I used the fertilizer that came with the GrowBox but I’m going to try it with some other fertilizers in the future. I’ll update this review when I have tried a bunch of options. As far as I know, you can only get that particular formula online from Garden Patch – I guess that’s one way they keep you coming back for more! Good luck with your GrowBoxes – they really do work well and I think you’ll enjoy using them instead of digging in the garden 🙂

  2. ginijean

    Great to come upon your site and hear your reviews. This was the first year using the Grow Boxes and I have to say I” love them”. I bought 3 and planted various plants. I will do things a little differently next year. I But I did really get a bountiful crop. I am also going to experiment with the use of fertilizers and like you, I am going to reuse the mat. In one box I planted 2 tomato plants and put an eggplant in the there too, It was very crowded but very prolific. The tomatoes were good, but the eggplants were excellent. However, next time, just two plants, as suggested. The next box I put two zucchini plants on one long side and 2 melon plants on the other. I figured I was well within the limits that were given. The zucchini went wild, yielding 45+ zucchini, but they squeezed out the poor melons. I took out the zucchini plants when I saw that they were failing (happy to do so) and spruced up the melons which I thought would just die off. They didn’t and now I have three little melons and a very strong vine. That was only 4 plants and they were very crowded so I’ll have to re-think this for the next year. I happened to have put two melon plants down in my vegetable bed and they are really doing good. One is the size of a small volley ball and the others are not far behind. The third box I put in Basil plants and a pepper plant. Basil took off and is still doing fine. The pepper plant continues to give more, but not one worth bringing into the house. They all got black blight, don’t know why, so I have to be careful of that combination. As you may have guessed, I Love Gardening. Good luck with the changes you will be making. I’d love to hear aboout the kind of fertilizer you’ll be using and so forth. Success, Yours, Gini

  3. Leanne

    I had a problem with end rot on my tomatoes and had to replace bell peppers twice. The plants did not do well and mature plants produced fruit that rotted before ripe and ready to pick.

    • Esther

      I have dry rot on one of my tomato plants too. I bought good soil from gardening place. Disappointed! I was told to put lime in water, but didn’t help! Any suggestions?

  4. Bill Strebel

    I am still waiting to see how my Grow Boxes do this year. My parents have had great luck with them over the last 2-3 years so I finally decided not to till and purchased 6. Unfortunately, it has been one logistic oops after another. The first shipment I received 6 bottoms, 6 tops but only 2 Nutrient Patches even though the documents stated 6 were shipped. I called and they sent out another shipment, supposedly nutrient patches. This time I received 4 of the Dolomite Soil Sweetners. I called again, they said they would ship by the speediest means. Friday at 3:30 I received notification that the shipping label was printed but unfortunately, no one called Fedex to tell them. to come pick it up 3 days later.
    I am still hopeful to get my plants in the ground by Tax Day which is safe day for No-frost in Mid TN. Will update once I have some news.

    Oh, and one point on the pins. Try cutting some synthetic Quarter Round the length of the grow box, drilling holes and putting long nails through them. One on each side will hold down the nutrient Patch and also keep the sides from Rolling as they are prone to do once you cut them or they get wet.

  5. Maria

    I just got 3 of them for Mothers Day but they do not seem to snap together. Have you run into this problem? Is this usual? I am wondering if the three we got are defective, if this is just as they are or if we did something wrong.



    • Hi Maria, and happy Mothers Day! When you say the GrowBoxes don’t snap together, what parts aren’t doing that? If you’re having trouble with getting the planter box to snap onto the reservoir, it does take quite a bit of force – line up the parts (make sure the pins sticking up from the reservoir are directly under the holes in the bottom of the planter box and the edges of the reservoir line up with the box) and then push down hard. We didn’t run into any problems when testing the GrowBox but I suppose defects are always possible. Please let us know if you’re able to get this assembled.

  6. bernard chavers

    I’ve had the original garden patch for 6+ years and its still growing strong- it show its age with stains and such but that’s OK! My Mom gave me 5 EBs for my birthday after I’d ordered my GP-isn’t that ironic? for my second planting of the Garden Patch I used one of my EB covers and it worked great. I now just use black plastic and a bungee cord. Over all I’d give the Garden Patch a **** rating. It is not as easy to set up and fill as I’d like but it does grow great vegetables and still works after 6+ years.

    • Thanks for sharing your experience with us, Bernie! I like your method of using a plastic cover (or I suppose any other weed and moisture barrier would work too) with a bungee cord to secure it – great idea! Glad to know the GrowBox is still going strong after 6+ years!

  7. Tim Blanchard

    got my Grow Boxes and put them together filled them with a garden grow mix from a local Garden Store,put down my nutrient patch and put 2 tomato plants in each box.The plants grew great,but all my tomato’s had rotted from the bottom up,others had big black spots on them.I got my plant’s from a local nursery and they looked fantastic,great color,no spots or usual tomato disease.They had full sun and I kept the water filled,what happened?

    • Hi Sandra,
      I’d use a good quality mix that’s specifically designed for use in containers. So not a “top soil” or “garden soil”. Personally, I’ve been using a new product from Miracle-Gro called Organic Choice Potting Mix with Moisture Control and Compost. Most potting mixes have no soil – they’re just a sterile mix of substances to which you need to add nutrients (fertilizer) in order to grow healthy plants. With the Miracle-Gro with compost already added, I seem to get better plants with less need for fertilizer. That’s not an endorsement of the product or a recommendation, just an observation on what’s worked for me. Espoma also makes a good organic potting mix.

  8. Joyce

    I have ten of these that are set up in a temperature controlled greenhouse here in Colorado. I outside gardened for years with issues stemming from weather to pests.Blossom end rot is common here in tomatoes, peppers, cucumbers and zucchini due to extreme temperatures changes and calcium deficiencies in our soil. I use Miracle Grows Earth Choice organic and natural potting mix, the nutrient patch and Dolomite from Garden patch and their support cages for all my boxes. I also use landscaping pins to keep the covers down and they work well. I have had very prolific harvests for the two years I have been using these boxes in the greenhouse. I grow just about everything from seed or seedlings saving my own seeds for the next years plantings. I am expanding my green house this year to add 10 more boxes for market growing.

    • Thanks for sharing your experience Joyce! It sounds like the GrowBox has worked well for you.

      You raise a good point about the effects of temperature changes and soil issues. Here in Tucson we have extremely hard water, soils are alkaline and temperatures swing from one extreme to the other – even using a GrowBox or other planter doesn’t completely resolve those issues (particularly the hard water and temperature swings) so we have to be careful to add enough soil amendments/nutrients to the potting mix to avoid problems like blossom end rot. It’s not the container that causes the problem – it’s the environment.

  9. JoeB

    Thanks all for the reviews and comments. I just ordered the growbox and was wondering how it would work out. Sounds like if I have the soil right it should work out well. I am planning on putting beef steak and cherry tomatoes in the box, one of each. If I have the crop it sounds like I might have, I will be ordering more boxes. Thanks Again


  10. Good morning! I was glad to see your review of the Grow Boxes. I was given three of them for Christmas and after reading up on them, I ordered three more. They appear to be a perfect solution for the tree roots that invaded my raised bed vegetable garden. Additionally, the watering reservoir is a huge plus – even less water wasted than with square foot gardening! I collect rain water and the run-off from our air conditioner and will most likely not have to run the hose very much. (We have city water, which adds up!)

    Anyway, so far so good with my plants – I have 10 varieties of tomatoes growing, plus a box with four varieties of peppers and one eggplant. (Grow Box doesn’t really encourage the mixing of different plant sizes, but I needed a place for the eggplant, and am trying to rotate all the nightshade family plants out of the one in-ground bed I’ve got.) I set the plants out about three weeks ago – we had three late, light frosts, so I covered everything with cardboard and the plants survived. Now, the seedlings are all taking off and I had to place some temporary supports just yesterday because of wind. I’ll be giving bamboo stakes and twine a go for a more permanent support solution. That’s a great idea. Thank you!

    Has anyone tried growing beans or Brussels sprouts in the grow boxes? I am considering doing this in the future but am a little skeptical over whether or not they’d be successful, since I haven’t seen any reviews about these veggies.

  11. Laurie

    Hi, I’m growing Blue Lake bush beans in one box. They look very green and healthy but no flowers yet after about 3 weeks. we’re in super humid Tidewater VA. We’ll see. I can post when flowers and fruit appear.

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