Root Development

Roots will grow "where you put the water"


Rapidly applied water is primarily moved by gravity, so it will shape out like the photo to the left - downward.

Slowly applied water is moved by both capillary action and gravity. It will shape out like the photo to the right.

The root area not colored (or watered) will not have adequate root growth (if it has any).
The faster you apply water, the more locations you need to apply it. Six "Slow-Drip" locations are Optimal!


This is what the Plant Rocket System is all about!

Slowly applied water - all across the soil surface

Massive - Thick - Healthy Roots

Maximum Yield from your Plant!




What's Next?


Proper irrigation scheduling as the plant matures

Root Development Phase

The Development of Larger Plant Root Systems


Watering Cycles - Nutrients - Soil

Understanding Horticulture (plant science) is key to long term success.

Steps for giving your plants larger & more healthy roots.


Watering & Nutrient discussions

 for various Phases of

Container Plant Growth





For a container plant (especially for annuals - plants that live for one season), there are several phases of growth where our clearer understanding and proper  adjustments will benefit various aspects of the plant. Here we will look at root expansion, how to optimize it and it's ultimate affect on yield and vigor.


Transplanting Note: To minimize shock it is best to avoid traumatizing the roots. This means that tearing open the root system with ones hands during planting should be avoided. If the roots seem to look like they overcrowded and circling, this does need to be dealt with. The least traumatic way to do this would be by using a sharp knife and cutting several vertical slits in the roots ball at three different spots around the root ball. This will stop the circling and encourage the roots to go out in new directions with the least trauma. Remember trauma kills some of the roots and sets the plant back as well as reducing vigor.



Phase I. The first week following transplanting.

This is the phase where a plant is subject to shock. The roots are generally small and sparse. The tiny "fibrous" roots have not yet begun to develop. It doesn't take too many adverse conditions at this point to cause plant death. When stress does occur during this time it may often be that failure does not happen right away, but shows up later. Many problems can be attributed to stress at phase I.

During the sensitive "Transplant" phase the soil should be kept moist not soaking. When soil is too wet - roots can't breathe. Yes the root system respires, takes up oxygen and uses this to convert sugars into energy. The plant wants a good combination of moisture and air for optimum vigor and health. Depending on the soil and temperature, watering during this phase should be daily to every other day. Use a quality moisture meter and check. The lower soil should never dry out, but the top should dry some. This is indicative of adequate air for respiration.


Also during the transplant phase avoid using strong nutrients. Typically the nutrients already in the soil are enough. Do not over-fertilize! Fertilizer is stimulating and a tender new transplant doesn't need stimulation. Wait until the plant has settled into its new container.


Phase II. Generally begins week 2. The plant has established itself and is ready to begin growing. The root system is still small however and now is the best time to focus on developing a large, full root system. There are a number of nutrients which will help the roots to expand, and watering practice is also very important during this ROOT DEVELOPMENT PHASE.



Consider; if we keep the soil too moist during this time where is the incentive for the roots to expand. They can get all the water and nutrient they need right there near the surface. The idea is to water deeply, make sure the soil is adequately saturated throughout the container - all the way from top to bottom. Then allow enough time between watering that the surface dries and the roots expand to reach the lower levels of the pot to get their water. Depending on evaporation and transpiration the soil near the bottom can stay wet for as long as a three days.

Slow drip watering can accomplish this deep penetration of the soil. Rapid application of water leaves portions of the root ball dry. Later we find the roots have not developed properly deeper in the container.

The Root Development phase is too often over looked and the gardener goes directly into focusing on top - foliar growth resulting in a 10 to 20% reduction in yield in the end. Large roots are so very important towards higher production.

So a typical watering cycle for plants in this phase might be 3 days at first and 2 days a weeks the following two weeks. See chart below.




Typical Watering




Daily to E.O. Day

Light / 5-10-5

Root Development 1


3 days per week*

Moderate/ 5-10-5

Root Development 2

3 & 4

2 days per week*

Moderate/ 5-10-5

Top Growth 1

5 & 6

3+ days per week*

Full / 10-9-5

Varies with Plant Type


3+ to 6/7 days*

Varies / 5-10-5

* Note! Soil types and temperatures can have a major effect on both evaporation and transpiration - check soil moisture to determine what your plant needs. These are "typical" recommendations only - given only to provide the reader with a starting point. Daily watering may be necessary - check!


The reason that the second week of Root Development can be less frequent is that the roots have already grown deeper into the soil from the previous week. Deep soil stays moist longer.


Often higher nutrient nitrogen levels are being recommended during this very important Phase II. Nitrogen encourages top / foliar growth. Phosphorous (2nd number) encourages "bloom" AND "root" growth. Let the plant complete its root development before encouraging top growth with higher nitrogen.



Phase III (Vegetative growth) and Phase IV (Fruit development) are periods when the plant will be needing to take up more nutrients and water. BEFORE these phases begin is when you need to have helped the plant to have a large enough root system in order to provide these nutrients.



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