Fertilizers and water

Manufacturers make fertilizers to use with “average water.” That’s fine, except that water in many locales is far outside that average range. Water may be too pure, for example, without much calcium; or it may be the opposite ? it may contain too many dissolved solids. The pH can be too acid or alkaline or the water may have a spike in one or a group of nutrients that affects the nutrient balance.
Sometimes one fertilizer doesn’t “agree” with the water or planting mix, but another fertilizer with different ingredients works well. It doesn’t necessarily mean that the first one was bad, just that it wasn’t good for the conditions in your garden.

If the plants seem to have nutrient problems, check out the symptoms in a marijuana grow book that discusses and illustrates common deficiencies. They are usually fairly easy to correct.

All water suppliers are required to test their water and provide the public with information about what it contains on request. All you have to do is call and ask, and they will send you the test results for the water they pipe to you. Sometimes this information is available on the web.

You can also have your soil or planting mix tested for pH and nutrients at a soil testing service. The tests are inexpensive and used by conventional gardeners all the time, so they raise no suspicion (as long as there is not marijuana leaf in the sample). Check out the Yellow Pages or the Internet for companies.

The mineral content of water and planting mixes affects the nutrients’ availability. These tests show you what’s going on regarding the medium and water. They are invaluable tools for making decisions about fertilizing the garden. For instance, one rockwool gardener was using very pure water that had very little calcium. The fertilizer, blended for “average water conditions,” didn’t contain enough calcium. It was apparent from a description of the symptoms and figuring total calcium listed in the water and nutrients. Adding a calcium supplement, calcium nitrate, to the water solved the problem.

The coming new age

Fertilizers and planting mixes are undergoing a new revolution as manufacturers integrate enzymes, hormones, plant stimulants and beneficial living organisms into their mixes. Many of these products really do work. Even though they may seem expensive, they are well worth the cost because of their effectiveness at improving stamina and growth.

Readers with grow questions (or answers) should send them to Ed at: Ask Ed, PMB 147, 530 Divisadero St., San Francisco, California 94117, USA. You can also email Ed at [email protected], and send queries via his websites at www.ask-ed.net. All featured questions will be rewarded with a copy of Ed’s new book, Best of Ask Ed: Your Marijuana Questions Answered. Sorry, Ed cannot send personal replies to your questions.