HYDROPONICS
Most growers report that a hydroponic system will grow plants faster
than a soil medium, given the same genetics and environmental conditions.
This may be due to closer attention and more control of nutrients, and
more access to oxygen. The plants can breath easier, and therefor, take
less time to grow. One report has it that plants started in soil matured
after hydroponic plants started 2 weeks later!
Fast growth allows
for earlier maturation and shorter total growing time per crop. Also,
with soil mixtures, plant growth tends to slow when the plants become
root-bound. Hydroponics provides even, rapid growth with no pauses for
transplant shock and eliminates the labor/materials of repotting if
rockwool is used. (Highly recommended!)
By far the easiest
hydroponic systems to use are the wick and reservoir systems. These
are referred to as Passive Hydroponic methods, because they require
no water distribution system on an active scale (pump, drain, flow meter
and path). The basis of these systems is that water will wick to where
you want it if the medium and conditions are correct.
The wick system
is more involved than the reservoir system, since the wicks must be
cut and placed in the pots, correct holes must be cut in the pots, and
a spacer must be created to place the plants up above the water reservoir
below. This can be as simple as two buckets, one fit inside the other,
or a kiddie pool with bricks in it that the pots rest on, elevating
them out of the nutrient solution.
I find the wick
setup to be more work than the reservoir system. Initial setup is a
pain with wicks, and the plants sit higher in the room, taking up precious
vertical space. The base the pot sits on may not be very stable compared
to a reservoir system, and a knocked over plant will never be the same
as an untouched plant, due to stress and shock in recovery.
The reservoir system
needs only a good medium suited to the task, and a pan to sit a pot
in. If rockwool slabs are used, a half slab of 12" rockwool fits
perfectly into a kitty litter pan. The roots spread out in very desirable
horizontal fashion and have a lot of room to grow. Plants grown in this
manner are very robust because they get a great deal of oxygen at the
roots. Plants grown with reservoir hydroponics grow at about the same
rate as wicks or other active hydroponic methods, with much less effort
required, since it is by far the simplest of hydroponic methods. Plants
can be watered and feed by merely pouring solution into the reservoir
every few days. The pans take up very little vertical space and are
easy to handle and move around.
In a traditional
hydroponic method, pots are filled with lava/ vermiculite mix of 4 to
1. Dolite Lime is added, one Tblspn. per gallon of growing medium. This
medium will wick and store water, but has excellent drainage and air
storage capacity as well. It is however, not very resuable, as it is
difficult to recapture and sterilize after harvest. Use small size lava,
3/8" pea size, and rinse the dust off it, over and over, until
most of it is gone. Wet the vermiculite (dangerous dry, wear a mask)
and mix into pots. Square pots hold more than round. Vermiculite will
settle to bottom after repeated watering from the top, so only water
from the top occasionally to leach any mineral deposits, and put more
vermiculite on the top than the bottom. Punch holes in the bottom of
the pots, and add water to the pan. It will be wicked up to the roots
and the plants will have all they need to flourish.
The reservoir is
filled with 1 1/2 - 3 inches of water and allowed to recede between
waterings. When possible, use less solution and water more often, to
pull more oxygen to the roots faster over time. If you go away on vacation,
simply fill the reservoirs full to the top, and the plants will be watered
for 2 weeks at least.
One really great
hydroponic medium is Oasis floral foam. Stick lots of holes into it
to open it up a little, and start plants/clones in it, moving the cube
of foam to rockwool later for larger growth stages. Many prefer floral
foam, as it is inert, and adds no PH factors. It's expensive though,
and tends to crumble easily. I'm also not sure it's very reusable, but
it seems to be a popular item at the indoor gardening centers.
Planting can be
made easier with hydroponic mediums that require little setup such as
rockwool. Rockwool cubes can be reused several times, and are premade
to use for hydroponics. Some advantages of rockwool are that it is impossible
to over water and there is no transplanting. Just place the plant's
cube on top of a larger rockwool cube and enjoy your extra leisure time.
Some find it best
to save money by not buying rockwool and spending time planting in soil
or hydroponic mediums such as vermiculite/lava mix. Pearlite is nice,
since it is so light. Pearlite can be used instead of or in addition
to lava, which must be rinsed and is much heavier.
But rockwool has
many advantages that are not appreciated until you spend hours repotting;
take a second look. It is not very expensive, and it is reusable. It's
more stable than floral foam, which crunches and powders easily. Rockwool
holds 10 times more water than soil, yet is impossible to over-water,
because it always retains a high percentage of air. Best of all, there
is no transplanting; just place a starter cube into a rockwool grow
cube, and when the plant gets very large, place that cube on a rockwool
slab. Since rockwool is easily reused over and over, the cost is divided
by 3 or 4 crops, and ends up costing no more than vermiculite and lava,
which is much more difficult to reclaim, sterilize and reuse (repot)
when compared to rockwool. Vermiculite is also very dangerous when dry,
and ends up getting in the carpet and into the air when you touch it
(even wet), since it drys on the fingers and becomes airborne. For this
reason, I do not recommend vermiculite indoors.
Rockwool's disadvantages
are relatively few. It is alkaline PH, so you must use something in
the nutrient solution to make it acidic (5.5) so that it brings the
rockwool down from 7.7, to 6.5 (vinagar works great.) And it is irritating
to the skin when dry, but is not a problem when wet.
To pre-treat rockwool
for planting, soak it in a solution of fish emulsion, trace mineral
solution and phosphoresic acid (PH Down) for 24 hours, then rinse. This
will decrease the need for PH worries later on, as it buffers the rockwool
PH to be fairly neutural.
Hydroponics should
be used indoors or in greenhouses to speed the growth of plants, so
you have more bud in less time. Hydroponics allows you to water the
plants daily, and this will speed growth. The main difference between
hydroponics and soil growing is that the hydroponic soil or "medium"is
made to hold moisture, but drain well, so that there are no over-watering
problems associated with continuous watering. Also, hydroponically grown
plants do not derive nutrients from soil, but from the solution used
to water the plants. Hydroponics reduces worries about mineral buildup
in soil, and lack of oxygen to suffocating roots, so leaching is usually
not necessary with hydroponics.
Hydroponics allows
you to use smaller containers for the same given size plant, when compared
to growing in soil. A 3/4 gallon pot can easily take a small hydroponically
grown plant to maturity. This would be difficult to do in soil, since
nutrients are soon used up and roots become cut-off from oxygen as they
become root-bound in soil. This problem does not seem to occure nearly
as quickly for hydroponic plants, since the roots can still take up
nutrients from the constant solution feedings, and the medium passes
on oxygen much more redily when the roots become bound in the small
container.
Plant food is administered
with most waterings, and allows the gardener to strictly control what
nutrients are available to the plants at the different stages of plant
growth. Watering can be automated to some degree with simple and cheap
drip system apparatus, so take advantage of this when possible.
Hydroponics will
hasten growing time, so it takes less time to harvest after planting.
It makes sense to use simple passive hydroponic techniques when possible.
Hydroponics may not be desirable if your growing outdoors, unless you
have a greenhouse.
CAUTION: it is necessary
keep close watch of plants to be sure they are never allowed to dry
too much when growing hydroponically, or roots will be damaged. If you
will not be able to tend to the garden every day, be sure the pans are
filled enough to last until next time you return, or you can easily
lose your crop.
More traditional
hydroponic methods (active) are not discussed here. I don't see any
point in making it more diffucult than it needs to be. It is necessary
to change the solution every month if your circulating it with a pump,
but the reservoir system does away with this problem. Just rinse the
medium once a month or so to prevent salts build up by watering from
the top of the pot or rockwool cube with pure water. Change plant foods
often to avoid deficiencies in the plants. I recommend using 2 different
plant foods for each phase of growth, or 4 foods total, to lessen chances
of any type of deficiency.
Change the solution
more often if you notice the PH is going down quickly (too acid). Due
to cationic exchange, solution will tend to get too acid over time,
and this will cause nutrients to become unavailable to the plants. Check
PH of the medium every time you water to be sure no PH issues are occuring.
Algae will tend
to grow on the medium with higher humidities in hydroponics. It will
turn a slab of rockwool dark green. To prevent this, use the plastic
cover the rockwool came in to cover rockwool slab tops, with holes cut
for the plants to stick out of it. It's easy to cut a packaged slab
of rockwool into two pieces, then cut the end of the plastic off each
piece. You now have two pieces of slab, each covered with plastic except
on the very ends. Now cut 2 or 3 4" square holes in the top to
place cubes on it, and place each piece in a clean litter pan. Now your
ready to treat the rockwool as described above in anticipation of planting.
If growing in pots,
a layer of gravel at the top of a pot may help reduce algae growth,
since it will dry very quickly. Algae is merely messy and unsightly;
it will not actually cause any complications with the plants.