Why And How To Prune Marijuana Plants
(Q) I've tried to read everything on pruning and
I still don't get it. My plants are almost a month old, have three
and four sets of leaves and seem very healthy.
(A) First off, you might not have to prune them.
Second, leaves are not usually the purpose or the target of
pruning.
Third, knowing why you prune, and what happens when you do so
will probably answer all the rest of the questions.
You Prune For Two Reasons:
1) To control the upward or outward growth of your plants. In
other words to keep them short.
2) To promote node sites (or bud sites). In other words to create
more branches (growing tips).
When you look at the main stem of the plant and how the leaves
grow from it, you will find it will be identical to any branch that
grows from it, or any branches that grow from them, etc.
So any reference I make to the main stem here, holds true for any
branches, or any branches that grow from those branches, etc.
The point at where a leaf joins the main stem (or branch) is the
node, at the node and just above the leafs' stem (petiole) you will
find a **bud**.
This bud will become a branch. Under the right conditions
branches will grow. Now, keep in mind that some varieties of plants
are good branchers, some are not.
Now let's assume the reason we're pruning is #2 above, to promote
node sites or branching. If you cut the top of the main stem off
then look at the plant, there will be some leaves and associated
nodes.
Since the top of the plant is gone, the growth energy that would
go there is now going to the remaining nodes because it has nowhere
else to go.
What you did by topping the plants was to FORCE growth at the
nodes thus promoting branching. The nodes nearest the light will
grow the fastest. You would do this if you don't want a plant to
grow too tall, but would rather want it to grow out.
If this is your first crop you'll understand much better what you
want once you've watched a plant through its entire life cycle.
If you topped the plant for reason #1, all the above would still
occur as a by-product, and most likely you would have to deal with
the top branches eventually becoming too tall.
(Q) Where exactly do I make the cuts?
(A) Appx 1/4 to 1/2 inch above the node that
will remain on the plant.
For cutting off leaves, cut them midway on the petiole.
(Q) Which set of leaves do I cut?
(A) You don't cut leaves off, you're just using
the leaves as an easy way to identify the node sites. I believe every
leaf feeds energy to its node site, cut off the leaf and the branch
at that node site may not develop as expected.
(Q) And why am I cutting them?
(A) Usually you don't cut leaves off unless
there dying, or you have a big fat juicy bud that's trying to grow
underneath a big leaf. If the bud would benefit from the light the
leaf is shading, you decide which you'd rather have :-)
(Q) My logic would be the more leaves the better
opportunity for photosynthesis.
(A) As long as the light can get to them.
The only leaves that are going to use the light are the ones
facing the light. A few leaves deeper into the canopy and the extra
leaves wont do you any good.
HID lights penetrate deeper into the canopy than fluorescent.
Side lit systems like the phototron require you to prune to
promote branching *AND* to remove larger leaves that tend to grow
nearest the lights in order for direct light to benefit the newer
inner branches.
The main reason this works in a phototron is the ability of the
side lighting to get under leaves that want to grow horizontally.
Without removing leaves near the light the phototrons fluorescent
wouldn't penetrate.
Top lit systems depend on light penetration qualities of the lamp
going through and around the leaf to do this.
I'd say a top lit garden would have enough leaves (full canopy)
when you don't see much light when looking up at the lights from the
bottom of the canopy.
A phototron is like a top lit garden only on its side and rolled
up into a circle. Its canopy are the sides of the unit.
One thing about pruning to remember is that one thick stemmed
shoot tip is being replaced by two or more much thinner shoot tips.
Buds may be more numerous but they will be smaller.
A pruning rule of thumb: The thinner the shoots, the smaller the
fruits.
(Q) I have seven plants and plenty of room .
Thanks in advance.
(A) As I said, you might not have to prune.
It wouldn't be a bad idea to do it on one plant just to get the
experience. Just be prepared for a shorter bushier plant than the
rest.
In the end you might find that 1 or 2 pruned plants can do as
well as the 7 you have now.
Books
Grow Great Marijuana:
An Uncomplicated Guide to
Growing
the World's Finest Cannabis
If you find instructions and books about growing hydroponic
marijuana overly technical and hard to follow, this book is a very
good choice for simple and accurate instructions. It does not cover
advanced techniques so if you already know how to grow, this book
would be of little value. But if you are a first time grower with no
experience, this is the first book to look at.
It will explain the steps involved from start to finish (with
text and images). Includes information on where to grow, type of
hydroponic system to use, selecting a seed strain, lighting, fans,
nutrients, security, clones, vegetative growth, flowering,
harvesting, stress, pests, and more. Recommended for beginners only,
this will show you everything you need to raise a hydroponic
marijuana crop.
Grow
Great Marijuana
Marijuana Horticulture:
The Indoor/Outdoor Medical Grower's
Bible
Over 500 pages with more than 1000 color images. If you were only
going to get one book about growing, this book would be the best
choice. Describes growing marijuana outdoors and indoors (with
hydroponics or soil).
Also provides information that you can refer back to when things
go wrong. A very comprehensive reference book for anyone interested
in growing marijuana, either indoors or outdoors. Recommended for
beginners and more advanced growers.
Marijuana
Horticulture
The Cannabis Grow Bible:
The Definitive Guide to Growing
Marijuana
for Recreational and Medical Use
A very good source of information covering all aspects of
growing, from seed selection to harvest, curing and more. Over 300
pages with almost 200 color and black-and-white photographs, charts,
and tables. Recommended reference book for indoor and outdoor
growers.
A great marijuana growing and breeding guide. Includes chapters
on seeds, propagation and germination, growing indoors, growing
outdoors, hydroponics, pre-flowering and flowering, predators, pests
and plant fungi, breeding, and more.
The
Cannabis Grow Bible
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Books About Growing Marijuana
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