When gardening outdoors, Mother Nature plays the major role of “care-giver” while the gardener lends a helping hand.  In nature, most plants will go many years with little or no pruning.  Yet when gardens are brought indoors, we as gardeners somehow feel compelled to prune, altering the basic growth pattern of the plant.  In most cases it is better not to prune a plant than to do it incorrectly.  Pruning WILL NOT improve the overall yield of a plant. This being the case, why do most gardeners feel that trimming their plants is important?  There are many good reasons to trim the growth on a plant and when done properly, the desired effect will always be achieved.  The main reasons to trim or prune indoor plants are as follows;
            - to maximize energy distribution throughout the plant;
            - to control the overall plant size;
            - to improve the overall quality of flowers, fruit, foliage, and stems;
            - to improve and maintain plant health and vigor.

Pruning WILL NOT lead to an increase in plant yield.  Pruning improperly can cause stress, serious damage to the plant, and an open wound through which disease and infection can infiltrate.  These factors alone or combined, can drastically effect the growth and fruiting/flowering production on a plant.  In extreme cases, improper pruning can even cause death. 

Pruning can be safe and effective in plants when done properly and with care.  This article is aimed at teaching the average gardener the proper and safe ways to prune a plant, thus limiting the risk of damage to the plant.  This will lead to success in the garden and the gardener achieving the desired effect with each plant every time.

There are certain concerns that come with pruning.  When trimming a plant, one essentially wounds the plant at the point where the cut is made, making the plant vulnerable to infection and disease.  The tools making the cuts whether scalpel, scissor, or shear, must be sterilized before each cut is made.  The easiest way to do this is to submerge the blades of the cutting tools in a solution of 4 parts water to 1 part bleach before each cut is made.  When the cutting tools are not properly sterilized before each cut, disease can be transferred from one plant to another.  This careless behaviour can cause entire crops to become diseased, costing the gardener time, money, and unnecessary stress.

To really ensure that no unwanted viruses or diseases can gain access to your plant, pinch the flesh of the plant between one’s fingers where the cut will be made.  By the end of the day the wound will have healed internally.  Trimming then will not leave the plant at such a risk of infection.

Another concern with pruning is the stress that the plant will feel and the energy used to heal and rejuvenate itself.  To limit these problems only trim the plant when necessary.  Before making each cut, consider the risk of damage to the plant.  Almost all trimming should be done before flowering sets to ensure the best possible outcome.Most indoor gardeners choose to prune their plants because of the limited grow space that comes from growing indoors.  To keep plants from growing too tall, gardeners use a method called “topping” the plants.  It involves simply cutting the top off the main stem of the plant.  Pinching the top off the main stem diffuses floral hormones causing the plant to focus on lateral growth, rather than vertical growth.  This means that plants will stay squat and become bushy. The same topping technique can be done on lateral branches to control lateral growth.  This will consequently cause the plant to focus on vertical growth unless it is kept in check as well.

There is an interesting effect that topping can have on the plant once it flowers.  Gardeners will find that plants that have had their main stem topped will produce more small fruit, where plants that haven’t been topped will grow fewer large fruit.  Identical plants where one has been topped and one hasn’t, the mass yield will be roughly the same, just the number of fruit will change.

When trying to grow large fruit or flowers, gardeners will actually control the number of fruit or flowers allowed to grow on the plant.  For example, if one is flowering watermelon plants and there are 6 flowers on each plant, the grower could choose to prune off 5 of the flowers.  This act will allow the plant to focus all its energy towards growing one large watermelon instead of 6 smaller ones.

One of the main reasons that indoor gardeners would prune is to effectively distribute the plants energy.  This basically means that gardeners must trim leaves damaged by insects, disease, temperature, nutrient disorders, and leaves not contributing to the plants health.  This allows the plant to direct energy away healing a damaged part of itself.  This energy could be better used towards new growth, root growth, and fruiting or flowering.

There is a “rule of thumb” when it comes to trimming damaged leaves.  This is to only remove leaves that are 50% damaged or worse.  Any leaves that are more than 5o% damaged are no longer providing adequate energy to the plant and therefore are no longer worth keeping. 

There is a common misconception that yellow leaves should be removed at first sight.  Yellow leaves are usually the sign of an on-going stress affecting the plant.  This might be a nutrient disorder, an insect problem, a light period interruption problem, etc.  Whatever the source of the problem might be, once it is corrected most gardeners find that those yellow leaves can green back up before long.  Leaving yellow leaves on for a while will save the plant much stress and will allow the plant a quicker recovery once the problem is solved.  If the source of the problem is not being treated, all the pruning in the world will not help.

There is another common misunderstanding among gardeners when it comes to pruning.  Many gardeners are told that trimming off the bottom 1/3 of the plant’s branches and leaves prior to flowering will lead to an increased yield.  They are told that this allows the plant to direct energy away from small lower branches that receive little light.  This energy can then be used towards flower production throughout the rest of the plant.  This may be the case but that does not mean an increase in flower yield. It simply means that the remaining flowers will be of better quality and will be larger than if the bottom 1/3 of the plant had not been pruned. When taking this approach, one must keep in mind that the lower parts of the plant including roots derive most of their energy from the lower leaves.  Pruning these lower leaves on a plant that still requires root development is not recommended.  If one chooses to prune the bottom 1/3 of the plant’s branches and leaves, it should be done 1-2 weeks prior to flowering.  

As we have just learned, pruning is not quite as necessary as we are often led to believe.  This does not mean that pruning does not have any benefits.  There are many benefits that are associated with pruning such as controlling plant size, efficiently distributing energy, and allowing the gardener to improve the size and quality of the fruits and flowers being grown.  Using the proper pruning techniques mentioned here will give the gardener the desired effect leading to success in the grow room every time.

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