Frequently Asked Questions

How large is the EarthBox?
The dimensions of the EarthBox are 29" L x 13.5" D x 11" H. It holds 3 gallons of water and 2 cubic feet (60 dry quarts) of growing media.

Does the EarthBox really work?
Our studies have shown that the EarthBox can double yields, using less water and fertilizer compared to conventional gardening. More importantly, thousands of EarthBox customers prove our claims every time they plant. We’re so sure that the EarthBox will work for you; we offer a one-year satisfaction guarantee. You can use the EarthBox all season long and if it doesn’t produce as advertised, simply return it, and we will promptly refund your purchase price.

What is the EarthBox made of?
All of the EarthBox components are manufactured from #2, #4, and #5 plastics, all of which are food-grade and recyclable.

What is the weight of the EarthBox when it’s filled with water and growing media?
The EarthBox weighs approximately 80 lbs. when filled. We offer a caster kit to make the mobility a lot easier.

What should I do if I have poor soil in my area?
Since the EarthBox uses growing media available at any garden center, soil conditions in your area mean nothing. In fact, many people have tremendous EarthBox gardens on their patios, balconies and decks.

Do I have to worry about weeds growing in my EarthBox?
No. Since the growing media in the EarthBox is covered with the mulch cover, weeds don’t even have a chance to start. There’s never any need to pull weeds or use herbicides.

When should I add water?
You can’t over-water so don’t try to regulate the moisture level in the growing media. Keep the reservoir filled. When the plants are small, add water every few days. As they grow larger, add water more often, and once a day for heavily fruited or mature plants. You can easily assess the water usage by the time it takes the water to pour from the overflow hole. Never let the reservoir go dry.

I think my plants are getting too much/too little water. Can I manually adjust the watering?
No. The EarthBox has been designed so that you can’t over-water and the only way to under-water is to let the water reservoir run dry. Remember, plants are taking the exact amount of water they need from the reservoir…no more and no less. Resist the temptation to second-guess the system, as this will only lessen results.

What time of day should I water my garden?
Water the EarthBox regularly when it is convenient for you. Just remember to never let the reservoir run dry.

What is Dolomite? Is it used only for tomato plants?
Dolomite is a source of calcium and magnesium and can be used for any plant, although it is critical for healthy tomatoes and other “seeded” vegetables, in general. Dolomite should be used for all “seeded” vegetables since they need a lot of calcium in order to produce healthy fruit; dolomite satisfies this requirement. It is also used to raise the pH of the growing media, since peat is very acidic. 

What kind of growing media should I use?
We have recommended several brands that will work best, but almost any brand of peat-based growing media for containers or hanging plants will work. You’ll need 2 cubic feet (60 dry quarts) per EarthBox.

What kind of fertilizer does the EarthBox need?
Each time you plant in the EarthBox, use 2 cups of a dry, granular fertilizer or plant food for vegetables (use 3 cups if the fertilizer is organic). The three numbers of the elements making up the fertilizer content (NPK) should be in the range of 5 to 15 (i.e.12-8-10, 10-10-10, 6-8-10) for non-organic fertilizers. After you have applied the fertilizer in the form of a strip, no additional fertilizer will be needed. 

Can I purchase supplies like fertilizer, dolomite and growing media at a garden center?
Yes. The Dealer Locator has information on all EarthBox registered retailers, but if your local garden center does not carry the EarthBox, please let us know.

How do I know when to fertilize my plants?
With the EarthBox system you fertilize only one time per growing season; when you first set it up. Use just 2 cups dry, granular fertilizer for vegetables (3 cups if using organic fertilizer), and the plants will have just as much as they want, when they want it. You can’t over or under feed. Avoid water-soluble fertilizers, as well as time-release fertilizers.

Can I use organic fertilizer?
Absolutely! Many EarthBox gardeners prefer growing their plants organically. We have recommended several brands of dry, granular organic fertilizers that can be used by placing 3 cups of organic fertilizer, in the form of a strip, in the EarthBox. We have also added an 8-3-5 certified organic fertilizer to our product list.

Can I use liquid fertilizer or fertilizers that are mixed with water?
Years of scientific research have gone into determining the type, quantity and placement of fertilizer to maximize plant health and production. Liquid fertilizers defeat the purpose of the EarthBox system, as nutrients are not provided on a constant stable basis. An occasional shot of liquid fertilizer, in addition to the fertilizer strip, is okay, but not necessary.

Can I use Osmocote® or other time-release fertilizers for the fertilizer strip?
No. Time-release, or "coated" fertilizers should not be used. Growing Media that already contains fertilizer is ok to use, but it does not replace the fertilizer strip. You should still add the fertilizer strip as you set-up your EarthBox.

Which type of grow light is best for my indoor growing needs?
Metal halide lights produce a strong output of the blue spectrum, which will result in strong plant growth. It is the best type of light to be used as a primary light source (if little or no natural sunlight is available).

What grows best in the EarthBox?
Commercial tomato growers invented the EarthBox, but you can grow virtually anything in it: peppers, eggplant, Brussels sprouts, cucumbers, herbs, flowers etc. Please refer to the Planting Guide to see what else you can grow.

Can I grow root vegetables (carrots, potatoes, garlic, etc.) in the EarthBox?
You can grow almost any root vegetable in the EarthBox, but keep in mind the depth of the soil is about 8 inches. While it may be fun to experiment with root vegetables, you may not get a substantial yield like you would normally with aboveground vegetables (tomatoes, eggplant, peppers, etc.).

Can I place different plants in the same box? If so, how many?
Refer to the Planting Guide. If the plants have the same planting configuration, they can be successfully mixed in the EarthBox.

Is it correct to place only 2 tomato plants in the EarthBox?
Yes. Through years of experimentation, we have developed the optimal number and arrangement of each type of plant. Please refer to the Planting Guide for a complete list.

Should I do anything special for tomato plants?
Most varieties require a higher pH level of growing media. Simply mix 1 pound of dolomite in the top 2-3 inches of growing media (before adding the fertilizer strip) to raise the pH. The EarthBox will do the rest.

What if I need support stakes for my tomato plants?
Tomatoes, cucumbers, beans and other vining plants need support. EarthBox now offers an optional Staking System that integrates with the EarthBox container. This eliminates the need for awkward wire plant cages or trellises.

How can I prevent splitting tomatoes?
Tomatoes will split when (1) there is a lot of heat and alternating rain or (2) if very dry weather is followed by days of rainfall. It is really caused by the drastic change in the amount of water in the fruit along with the heat. You can cover your plants with shade cloth to cut the amount of heat and always remember to keep the water reservoir full so the plants always have a consistent supply of water.

What can I do to prevent black spots on the bottom of my tomatoes?
The black on the bottom of your tomatoes is called Blossom End Rot (BER). It is caused by a lack of calcium and other ingredients in the growing media. Adding 1 pound of Dolomite to the growing media before planting (as in the instructions) can help prevent BER from forming. In the event BER still presents itself, mix ¼ cup of hydrated lime or pickling lime with one gallon of water and add it to the reservoir the next time you fill your EarthBox with water. Do this only once and pick off the affected tomatoes. This may also occur with other “seeded” vegetables, such as peppers.

What can I do if beetles or tiny black bugs are on and near my plants?
Spray with an all-purpose natural insecticide solution, which has been approved for organic gardening, and will also help treat other pests like aphids, cabbageworms, leaf miners, and fruit flies.

What can I do if hornworms or other chewing worms are on and near my plants?
Spray with BT (Bacillus Thuringiensis), a very good bacterial solution for caterpillars and other types of chewing worms. Once ingested by the pest, the bacteria will kill the caterpillar. This is not a chemical and will do no harm if sprayed on the skin.

Can I remove the mulch cover once the plants have started growing?
No, you should never remove the cover until your growing season is finished and you’re ready to replant. The EarthBox mulch cover is an integral part of the EarthBox gardening system. The cover helps to keep your growing media moist; it keeps rain from washing away your fertilizer, and it helps prevent weeds and other unwanted plants from getting into your EarthBox.

Is the EarthBox reusable? How do I replant my plants?
Absolutely. Simply remove your old plants, the old fertilizer strip and some of the surrounding growing media. Decide what you are going to plant in your EarthBox and refer to the Planting Guide to know where the fertilizer and plants need to be placed. Top the EarthBox off with some fresh growing media, creating a mound. Mix in 1 cup of Dolomite to the growing media. Based on the Planting Guide, pour 2 cups of dry, granular fertilizer (3 cups if using an organic fertilizer) in the form of a 2-inch-wide strip, burying it 2"-4". Put a new mulch cover on your EarthBox and replant. You can use the same growing media up to 6 growing seasons, and the EarthBox for many years.

Is it necessary to remove the growing media to prevent frost from breaking the container during the winter?
In order to prepare your EarthBox for winter, we recommend you remove the old plants, mulch cover and fertilizer. Place a new mulch cover on your EarthBox and drain the remaining water from the reservoir by tipping the EarthBox towards the overflow hole.

How long from the time I place the order until I receive it?
Based on our current Shipping Policy, you can expect your order to arrive in 4-8 business days from the time your order is placed. Orders shipping to Hawaii, Alaska, and U.S. territories may take up to 3-4 weeks due to customs.

Can I ship to a different location?
Yes, but shipping charges will be based on the products going to each separate location.

Do you offer personalized greeting cards?
Yes. To include a personalized greeting with your shipment, simply fill out the designated portion of the order form during checkout.

Where can I purchase EarthBoxes near my home?
The EarthBox is available at fine retailers across the U.S., Canada, UK, and South Africa. Our Dealer Locator has information on all EarthBox registered retailers, but if your local garden center does not carry the EarthBox, please let us know.

How many years can I expect my EarthBox to last?
We are proud to say that we still have EarthBoxes in use today that are over 15 years old.