A Test to Know if You Grow With Optimal Soil Moisture?

In my previous two posts - Maximizing Root Growth in Containers - I talked about maximizing the area where roots grow (Thereby increasing overall plant growth and yield) by keeping the entire soil moist with mulch and trying different types of soil amendments to keep the moisture at the optimal level.  I have also written a more scientific look at soil and water availability.

I want to reiterate that the most common problem I see with indoor growing is over watering, but just like too much water is bad, too little water is not good growing either. I have on occasion gone away for a week or more. I watered the plants well before I left, and when I got back, they were not wilting but the soil was very dry. I watered the plants and in two days, I could easily see growth.  I  could see the soil and pots through the leaves when I returned, but two days later, the leaves /plants had grown so much that I could no longer see the soil/pots.
What happens when the soil moisture gets low is that little holes in the plants called stomata close to conserve water. The good news is this keeps the plants from wilting or dying for a while. The bad news is that carbon dioxide ENTERS the plants through the stomata. This means that photosynthesis will come to a halt and the plant will basically just sit there, not growing, and not wilting.
I have used a soil moisture meter, from HTGSupply.com. However, I lost it when I moved a couple years ago, and I have been using sight and the tip method in my greenhouse. First, get to know the color of your grow medium when it is wet and dry. My soil is a dark almost black color when wet, and brown when dry. Second, when the top is brown (or dry looking), I tip the plants and feel how heavy they are. If the plant is very light, and almost falls over with a little push on the pot, it is very dry and needs a lot of water. If the pot is heavy, I just give the plant a bit of water to darken the soil on top. If your plants do get very dry (easy to tip) You may want to water them two or three times with small quantities of water. Water is cohesive, meaning it sticks to itself. So, if your soil is very dry, the water will run right out. If you water a 1-2 gallon pot and water runs out in a second or two, you have very dry soil. Give it a few light watering's and you should notice the water is staying in the soil/pot.

You want to make sure you soil is wet, so that plants are not water stressed and keep their stomata open, but not too wet (soggy) where plants roots suffocate and plant growth stops and leaves yellow.
Good Growing,
Dr. E.R. Myers


Maximizing Root Growth in Containers -2

In my previous post, I suggested trying to keep the top layer of soil moist to maximize root growth. This month I am encouraging and trying some new techniques myself to expand our growing abilities You hydroponics growers, I know this blog does not always give you the attention you deserve, but different hydroponic mediums might suit the plants better than the ones you are using, why not try a different medium?  Of course you will have to experiment with watering amounts and timing if you use a different medium.

Even if the ‘new ‘medium is not an improvement, at least you know, and the knowledge you gain through observation may come in handy sometime in the future. Expanding your knowledge is like planting an unknown seed; you never know what it will grow into.

Think about the type of soil you use. . You could try different soil amendments. If you are using a cheap soil from a retail store, you can do better. Even if you are using a top rate soil please read my post on vermiculite and perlite and coir and think about your growing situation. I tried a coir soil mix and continue to do so. 

Is your soil dry every day when the plants are large and flowering? If so you need to add materials like coir or compost to the soil, or add less sand or perlite to your mix. I encourage you to do a scientific experiment, use two different mediums in a few different pots and compare the plants. (Click here to read a post on the characteristics to use when comparing plant growth)

Good Growing, Dr. E.R. Myers


Maximizing Root Growth in Containers -1

I have written posts about How to Water properly,  soil and water availability, and about growing in small spaces.  The problem is even good growers cannot keep potting up to bigger and bigger pots to allow for bigger root masses. If you want to maximize root growth which can maximize yield and prevent disease there are some techniques you could try. A lot of container space often goes unused, because roots usually do not grow into the top few inches of soil/container. Roots generally grow towards gravity but the soil at the top of containers is often dried out from powerful lights and low humidity. Although I should mention the #1 problem I reply to is over watering. You want to find the Goldilocks of soil moisture, not too wet, not too dry.

If your pot is over one foot tall and like most growers you don’t have roots growing in the top 1-1/4inches, you are wasting 10% or more of your soil. I would wager many people waste up to 25% of the space in their pots. You should always use tall skinny pots if possible. If you use pots that are wider at the top than the bottom, the amount of wasted soil is even greater!

I have written about compost, one suggestion would be to use compost as a mulch to keep the top of the container/soil moist; the added benefit is it would also supply organic nutrients and beneficial bacteria to your plants. The down side is compost from outside could have pests, and it could attract or be food some pests too. You could try using a layer of coco coir as a mulch layer. One benefit is that because it is fibrous, water will pass right through it. This means you can fill your pot to the very top without worrying about water spilling over the sides. The coir will dry out much faster than soil, you can notice this with a color change, coir will change from dark brown (wet) to light brown (dry). If you are mindful of the soil under the coir you can keep your soil moist as the coir shields the soil from the lights, and slows soil water evaporation. Allow the coir to stay dry for a day or three. (You can use the finger test - stick your finger through the coir and into the soil to see if the soil is wet – to determine if you should let the coir dry out one or three days). A soil meter is also a tool that could help. You want the top layer of the soil to be damp, not soaked.

You could try this with other materials like perlite or vermiculite, but be careful not to use anything heavy that might compact your soil the way putting pebbles would.

Good Growing
Dr. E.R. Myers


How to Tell if Seeds Will Germinate

The idea for January 2013 is to try something knew. I want to first and foremost say this is not going to work for all seed types, obviously orchid and basil seeds and other plants with small or very large seeds will behave differently. Basically, if you soak a seed overnight it should sink. If it floats it will not germinate. You just put some seeds in a cup/container and in the morning the one’s that sink are ready to be planted. The problem with this is you may actually be simply selecting for seeds that sink and not planting all the viable ones. Worse, you could throw away valuable seeds. If you only have a few seeds, the best thing would be to plant them all.

If you have a lot of seeds and wonder if most of them are still viable (will grow) you can use the paper towel method. Put 10 or 25 seeds on a moist paper towel in a plastic bag. After a week, see how many have germinated. If you started with 10, multiply the number that germinated by 10, and that is the percentage you can expect to germinate, if you used 25, multiple the number that germinated by 4 to get the percentage that you can expect to germinate.

Example: You place10 spinach seeds on a paper towel and 7 germinate after a week. you can expect 70% (10 x 7 = 70) of the seeds to germinate.

Good Growing,
Dr. E.R. Myers


Can You Improve Seed Germination?

As we start another year, it is a great opportunity to try to improve how we grow.

Once you can successfully grow the plants you want to grow, why not try to grow different plants?  I have posted about growing banana's and ghost peppers why not give something else a try? Of course we all can improve how we grow if we are mindful and observant. My theme for January will be to take us through the grow process and think of ways to make an improvement in growing.
Germination I have done a scientific test that I encourage you to read in regards to germination,  comparing Rockwool, soil and grow plugs, .  I encourage you as always to try this for yourself.   If you have not tried the plugs, give them a try, for the most port they are made of materails that would otherwise be a waste product (tree bark and coconut husks).  They are also very easy to use, you sow the seeds and then just plop the plug in the soil or hydroponic system like the big boy, once the plants start to grow.

Do you use a heat mat? As I mentioned this in a previous post that you can speed up the germination, but it can also increase the percentage of seeds that germinate

Please see my post on seed storage. I do not think you can find a better way to store seeds than in the freezer, accept a -70C freezer like they use in scientific laboratories.

Good Growing,
Dr E.R. Myers