All About the Gro-System

What is the Diamond Bar Gro-System?


The Diamond Bar Gro-System is a line of self-watering pots that offers a complete, balanced growing environment for a wide variety of plants. Each of these durable, self-watering containers comes filled with professional-grade potting mix and includes a quart of balanced fertilizer. This three-part system (potting mix, fertilizer, and self-watering pot) was developed over years of testing to counteract two major problems facing container gardeners throughout the western states: 1) high pH in both primary and secondary water, and 2) hot, dry weather.  These issues are explained below.  When used properly, the Gro-System enables plants to flourish with less work. “Better Quality, Less Maintenance”; that’s our motto.

How Self-Watering Pots Work

Self-watering pots are designed to make growing in containers easier by holding water in a Reservoir below the main bulk of potting mix. Each pot waters plants from the bottom up, mimicking the natural water table of the ground.  To fill the reservoir, simply poor water down the Fill Tube.  The Drain Spout has been provided to prevent the potting mix from washing out if too much water is added.  A Wick (in our case, a plastic tube packed with highly absorbent potting mix) soaks up the reservoir water/fertilizer, bringing it to plant roots where it’s needed. This wicking action is known as capillary action. Self-watering pots are especially helpful in hot, dry regions where keeping potted plants moist is a major challenge.

What’s wrong with regular pots?

How frustrating it can be to purchase beautiful hanging baskets in May, only to have them die a few months into the growing season. Inevitably, most regular hanging baskets and small pots dry out multiple times a day – demanding more and more attention to keep them moist as the plants grow larger. For even the most devoted gardeners, missing just one of these (seemingly hourly) waterings, could cause plants to quickly wilt and wither, ruining the investment of hard work, money, and (not to mention) pride.

After trying out various self-watering containers from many companies, we learned that the water reservoir in most self-watering pots is too small to make a difference in our climate.  So, we designed our own. Each 16” round pot boasts a 2 gallon water reservoir, and each 4′ oval pot holds 7 gallons. This larger water capacity enables more consistent watering, preventing the extreme conditions of regular pots: full saturation on one hand, and complete dryness on the other.

The pH Problem

Many plant problems persist throughout arid regions because of poor water quality. High levels of lime (calcium bicarbonate) and other minerals which naturally occur in the Rocky Mountains dissolve into runoff, making the water “hard”. Over time, this high water pH turns soils alkali. Many trailing type plants, including most hybrid petunias and million bells (calibrachoa), do not tolerate such conditions well. Although they may do alright at first, after a while, their roots can no longer absorb fertilizer and the plant suffers from lack of nutrients. They thrive in more neutral (and even slightly acidic) environs.

The Gro-System “Solution”

The Gro-System addresses the pH problem in two ways: 1. Balanced Fertilizer, and 2. Reservoir with ultra-absorbent Wick. After years spent trying out numerous fertilizers, we have selected a product particularly well-suited to the high pH of western waters. It has been formulated with a special Iron and Magnese combination intended to keep the pH in balance. The capillary wicking action made possible by our high-grade potting mix helps lower the pH because it holds fertilizer with the plant, preventing the leaching (flushing) which would otherwise occur with each watering.  This enhances nutrient uptake.  A quart of our blue liquid fertilizer concentrate comes with every Gro-System, but it’s also sold separately.

What’s in the Mix?

In containers, plants need a growing medium that is relatively light, holds moisture, and drains well. For the most part, potted plants do not depend on potting mix for nutrients, only for a healthy root environment. We have tested many growing mixes and have selected our favorite, Sunshine SC1 Mix (by Sun-Gro Horticulture), to include with the Gro-System. This professional-grade potting mix contains a blend of the highest quality Coir (ground coconut husk all the way from Sri Lanka), Canadian Sphagnum peat moss, and Perlite. It comes pre-charged with starter nutrient to give your plants a jump start. It holds moisture better than any other mix we’ve tried and is durable enough to use in the same pot for several years. Replacement potting mix is available at our store when needed.