Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02358839 2001-10-11
TEM File No. 226.4
POTTING ARRANGEMENT AND METHOD USING PUMICE
s FIELD OF THE INVENTION
The present invention relates to a potting system for use with plants, and in
particular for using a rock material in a novel potting arrangement and method
for
improved water and nutrient delivery to potted plants.
1o BACKGROUND OF THE INVENTION
Tropical and flowering plants are able to thrive and grow when supplied with
adequate and timely delivery of light, temperature, water and nutrients.
Plants absorb
water and nutrients through their root systems, and current water delivery
methods have
limitations in effectiveness and ease of use. An alternative process providing
significant
1 s gains in efficiency, consistency and conservation is presented further
below.
There are currently two basic types of cultivation systems employed for
household
plants: 1 ) Soil based, and, 2) Soil-less (termed "hydroponics").
1 ) Soil Based Cultivation
Soil based cultivation consists of a plant whose root system is contained
within a
2o growing medium of loam, peat moss and a variety of organic and inorganic
soil
amendments. The natural capacity of the growing medium as a nutrient source
for the plant
is augmented with additional fertilizer supplied either by mixing it in solid
form into the
medium itself or added with a water-soluble fertilizer. It is standard that
the container,
usually a pot made of plastic, ceramic or clay, is required to have at least
one drain hole in
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the terminal or bottom end to facilitate drainage after watering to prevent
root-rot and
oxygen deprivation. Water and fertilizer are periodically administered from
the top and the
excess escapes through the drainage holes at the bottom end. Typically a catch
tray is
placed underneath the pot to prevent damage to underlying surfaces.
Some limitations with this methodology are as follows:
a) Frequent watering is required.
The growing medium does not typically retain more water than is required to
completely wet the medium. The soil only has the capacity to retain the amount
of water
that completely wets the surface of each of the soil particles, which is small
in proportion
1o to the total volume of the soil. The plant usually consumes this water
rapidly, requiring
another watering cycle soon afterward, repeated ad-infinitum.
The holes) at the bottom end of the container allows excess water to drain out
the
bottom, preventing rot of the plant's root ball. While this is good for the
roots of the plant,
the user, or "gardener", frequently under-waters the plant to prevent
excessive spillage out
the bottom of the container, since the only indication that complete wetting
of the soil has
taken place is by water leaving the pot out the drain hole. This leads to
frequent watering
of the plant and inconsistent soil moisture, with the gardener never really
sure whether the
plant is getting the requisite amount of water and nutrients. The soil is
therefore typically
either too wet or too dry.
2o In many cases, peat moss is the principle constituent of a traditional
potting
medium. This is almost always the case with nursery grown flowering plants. In
such a
system, the plant is wetted during the watering cycle as usual, but peat moss
has a
tendency to shrink when dry. If this occurs, then the potting medium pulls
away from the
sides of the container and when a watering cycle occurs, most of the water
drains down
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along the inside walls of the pot, leaving very little wetting of the soil.
The only way to
then completely water the plant is to essentially submerge the entire root
ball until
completely soaked in another container of some kind that has been filled with
water.
b) It's wasteful of both water and fertilizer.
Under normal circumstances, fertilizer is injected into the water during a
watering
cycle. Since the gardener typically supplies the plant with water until fluid
is seen
escaping the pot out the drain hole in the bottom, fertilizer is therefore
also escaping out
the bottom of the pot through the drain hole.
c) It's inefficient.
1o Because of the need to water the plant frequently with no real
determination of a
truly accurate amount of nutrient provided, and given that most plants require
vastly
different watering cycles, the gardener is left with the task of keeping an
inordinate amount
of information about which plants to water, when and how much. If any of the
cycles are
missed, the plant suffers greatly, and so many houseplants do not thrive. In
the case of
flowering houseplants, most people do not expect them to last more than a few
weeks.
2) Non-soil (Hydroculture) Cultivation
Hydroculture is the term used for growing plants where the root system is
contained in an inert, pH neutral growing medium. Water-soluble chemical
fertilizer is the
plant's sole or primary source of nutrients, and is introduced either as a
solid during the
initial planting in the inert growing medium, or on a period basis via
watering.
Typically, the container used is a pot-within-a-pot system. The inner pot is
typically a mesh or other water permeable material that allows water to enter
and surround
the inert growing medium. The outer pot is a closed vessel that acts as a
reservoir for the
nutrient solution.
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Some advantages of this methodology are:
a) It's effective.
The roots of the plant are supplied with water and nutrient as they are
absorbed by
the inert growing medium. The plant has the ability to absorb as much or as
little of the
nutrient that it needs.
b) It's consistent.
The roots of the plant are continuously in contact with the appropriate amount
of
water and nutrient. The gardener also has the capacity to regulate the amount
of water and
nutrient that the plant is continuously in contact with. Further, pH
requirements are easily
to regulated via the nutrient solution.
However, this method also has several disadvantages such as:
c) It's time consuming.
When a gardener wishes to transplant a plant that has been started in a
traditional
growing medium (such as potting soil), the gardener is required to: 1 ) remove
all of the
15 soil from the roots of the plant; 2) completely wash the roots of the
plant; and, 3) very
carefully re-pack the roots of the plant into the growing medium.
d) It's difficult to transplant a plant whose roots have completely filled the
original container.
Transplanting from soil base to hydroculture is typically recommended for
smaller
2o plants. In cases where the root mass has entirely filled the growing
container in a soil
based medium, it is very difficult to transplant to hydroculture. Most nursery
grown plants,
and especially flowering houseplants, are sent to the retailer in rootbound
condition.
What is therefore desired is a novel method and arrangement which overcomes
the
limitations and disadvantages of the existing cultivation systems, as set out
herein.
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SUMMARY OF THE INVENTION
The present invention has most or all of the advantages of the two previously
described methods. It incorporates an inert, readily available volcanic rock
material to
provide a plant that is growing in a traditional soil based medium the
benefits of a
continually watered hydroculture system.
The present system has two general aspects: 1 ) The standard soil based
growing
medium in which the root ball of the plant sits; and, 2) a reservoir for fluid
that is
continuously supplied to the plant via capillary action. This fluid is
contained in a layer of
inert, pH neutral pumice volcanic rock that has preferably been thoroughly
washed. Due to
the porosity and pore structure of the pumice material, it exhibits strong
capillary action
properties. This layer of pumice rock sits beneath the root ball of the plant
in the base of
the pot.
In the present system there are several important features to consider:
a) It is a single pot system.
The container of a first embodiment of the present invention differs from the
usual
soil based growing container in that no drain holes are provided at the bottom
end of the
container or pot. This allows for the pumice layer in the bottom portion of
the pot to be
filled with an appropriate amount of fertilized water, which is then readily
available for
supply to the plant. In a second embodiment of the invention, a meshed
overflow drain
2o hole is provided part way up the side of the pot, near the top of the
pumice layer, for
escape of excess water in the event that a user overfills the bottom portion
to a level above
the pumice layer. Alternately, the meshed overflow drain hole may be
substituted with
numerous smaller holes about the pot at the same level to avoid using a mesh.
In a third
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embodiment, a perforated insert is placed within either of the first or second
embodiments
of the pot.
b) The water is delivered to the plant continuously, via capillary action.
As is the case in a hydroponic growing system, the water and nutrient are
delivered
to the plant in a continuous fashion, as required by the plant. The root ball
of the plant
draws water from the soil medium in which it is growing, which in turn causes
the soil
medium to draw water up from the pumice layer beneath it. The pumice layer
supplies
water to the growing medium via the naturally occurring capillary mechanism of
the
pumice material.
to c) A plentiful amount of oxygen is supplied to the plant.
A vital component of growing plants is to supply the plant with enough oxygen.
During the above-noted capillary action, the effect of water leaving the
bottom reservoir
and traveling up into the root ball draws ambient air down into the reservoir
to fill the
voids occupied earlier by the water. As well, the porosity of the pumice is
such that it
retains air. Hence, an abundant supply of oxygen is made available to the
plant.
d) Water needs to be supplied only on a periodic basis.
Since the base of the pot of the present invention is closed, the pot can be
filled to
the top of the pumice layer with fertilized water. The plant sits directly
above the pumice
layer in the soil-growing medium. Since there is a large, continuous supply of
water and
20 nutrient at the base of the pot, the plant can flourish in an environment
where watering
cycles are less frequent. The plant only needs to be watered when the gardener
determines
that the reservoir in the base of the pot is dry or drying out. Water is
evenly distributed
throughout the pumice and the growing medium, and so dryness is easily
determined by
observation or feel of the topmost layer of the growing medium.
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e) It's extremely effective.
The capillary action of the pumice rock provides the plant with an appropriate
amount of water and nutrient all of the time (as long as there is water in the
pumice layer)
because the plant is drawing the water only on an as required basis. Instead
of "drowning"
the plant and then letting it dry (as in the above discussed prior art
methods), the plant is
allowed to determine and serve it's own water requirements, without any
intervention from
the gardener.
f) It doesn't waste anything.
Instead of the gardener having to guess at the right amount of water and
fertilizer to
1o supply to the plant in a given watering cycle, the base of the pot is
simply filled to or near
the top of the pumice layer. Water is not wasted by escape from the bottom end
of the pot,
and all of the supplied fertilizer is absorbed by the plant.
g) The plant is easy to transplant.
Any root bound nursery grown plant is easily transplanted. The gardener simply
prepares a new container with the bed of pumice rock according to the present
invention
and then removes the plant from the old container, including the soil, and
places the plant
directly upon the pumice bed in the new container.
h) Spillage is avoided.
In one embodiment of the pot there is no water runoff after the watering
cycle, and
2o so the gardener is free to place the plants wherever desireable without
fear of water
damage to the supporting base, such as good furniture, wooden table tops, etc.
i) Fertilizer may be pre-applied.
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A water-soluble slow-release fertilizer may be added to the pumice (whether
washed or not) for absorption by the soil and the plant. The pumice layer
therefore forms a
desireable nutrient reservoir.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
Embodiments of the invention will now be described, by way of example only,
with reference to the accompanying drawings, wherein:
Figure 1 shows an elevated cross-sectional view of a potting arrangement and
method according to a ~lr~.t preferred embodiment of the present invention;
Figure 2 is a view similar to fig.l showing a second embodiment of the
invention
wherein a meshed drain hole is provided above the base of the pot;
Figure 3 is a cross-sectional view of a third embodiment of the invention
showing a
perforated insert placed within a pot lacking a drain hole as in fig. l ; and,
Figure 4 is a transparent view of the insert of fig.3 showing a layer of
pumice within the insert, and in addition illustrates an alternate version of
the third
embodiment wherein numerous small drain holes are provided above the base of
the pot.
I IST OF REFERENCE NUMERALS
10 plant stem
12 roots or root system
14 water
16 water source
20 pot
22 base of 20
_g_
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24 sidewalls of 20
26 bottom portion of 20
28 top portion of 20
30 pumice rock
s 32 soil
34 water flow through 32
36 water migration from 26 & 30
to 32 & 12
40 drain hole
42 mesh of 40
smaller drain holes without
44 mesh
50 insert
52 solid upper wall portion of
50
54 perforated lower portion of
50
is 1~F~C'RTPTION OF EMBODIMENTS OF THE INVENTION
With reference to figure 1, a stem or stalk 10 of a plant with a root system
or ball
12 is shown located, or "potted", in a potting arrangement according to one
embodiment of
the present invention. The potting arrangement includes a pot 20, which may
also be
referred to and known as a container, vessel, or the like, having a base 22
and outwardly
2o sloped sidewalk 24. The pot 20 is of a common and popular shape for
illustrative
purposes, but it will be appreciated that various shapes and configurations
will be suitable
for use herewith. An important difference of the pot 20 over prior art pots
used in soil
based cultivation is that the pot 20 lack or omits any water drainage holes or
outlets in the
base 22 and elsewhere. Hence, whereas prior art pots for soil based
cultivation require a
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form of water drainage outlet in the base to prevent root decay or rot, the
present pot 20 is
designed to contain any water 14 in a bottom portion 26 thereof, as applied
from a
watering source 16 for instance. It is understood that the term "water"
includes any liquid
suitable for use with plants which may or may not contain fertilizer or other
soluble and
non-soluble plant nutrients.
In the potting system of the present invention, a layer of crushed pumice rock
30 is
laid out in the bottom potion 26 of the pot as shown, to form a water
"reservoir". Good
results have been achieved with pumice rock of between 3/8 inch to 3/4 inch
diameter.
The root ball (i.e. roots and surrounding soil) of the plant to be potted is
then inserted into
to the pot above the pumice layer in a top portion 28 of the pot, and
additional potting soil 32
or like plant growth medium is added around the root ball to fill the pot as
desired. The
soil is not to be mixed with the pumice rock 30. The soil and pumice rock are
kept in
distinct layers as much as possible, although over time some soil will migrate
into the
pumice rock zone. For optimum performance, the pumice rock should be
thoroughly
cleaned by washing away silt or other materials which might be clogging the
pores of the
rock, prior to placing the rock into the pot. The volume of rock provided
depends
somewhat on the frequency of watering desired by the user - less rock being
provided for
more frequent watering, and vice versa. Typically, however, when using a pot
of the type
shown in fig. 1, the height of the pumice layer H 1 should be a minimum of
about I /4 of
2o the height H2 of the soil layer 32.
Once the plant 10 has been potted as described above, it may be watered from
the
water sourcel6 in the same manner as any soil based system. However, in the
instant case,
enough water should be provided so that the water will flow through the soil
(as indicated
by arrow 34) to not only wet the soil 30 but soak the pumice 30 by
substantially filling the
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pumice reservoir 26 with water. As a rule of thumb, the user should add a
volume of
water which is half of the volume of pumice placed at the bottom of the pot so
as not to
overfill the bottom portion 26. For example, a 500 ml bed of pumice should
hold about
250 ml water. Over time the user will develop a "feel" for the watering
requirement as the
user gets acquainted with the present system.
In a second embodiment of the invention shown in figure 2, a drain hole 40 is
provided in the sidewall 24 of the pot. In this embodiment the same reference
numerals
are used to identify the same or substantially similar elements from the first
embodiment.
The drain hole 40 is preferably located just above the pumice rock layer,
namely at a
1o height H3 of about 1/4 to 1/3 of the total height of the pot (which is at
least H1 + H2 in
fig. l ). The drain hole 40 ensures that a user can fill the bottom portion 26
with water
without over-filling the pot, so as to avoid drowning the roots 12 and soil 32
above the
pumice rock. Hence, in the event that a user overfills the base while watering
to a level
above the pumice layer in the bottom portion 26, the excess water merely
escapes through
15 the overflow drain hole 40. A mesh 42 should be placed in the hole to
discourage escape
of the soil 32. It will be appreciated that the size of the drain hole may be
varied,
depending on the rate of water escape desired. More that one drain hole may be
provided
about the pot if required.
In a third embodiment of the invention shown in figures 3 and 4, an insert 50,
or
"basket", is placed within the pot 20. In this embodiment the same reference
numerals are
used to identify the same or substantially similar elements from the first and
second
embodiments. The insert has an upper portion with sloped solid walls 52 for
holding the
soil 32 and root ball 12, and a meshed or perforated sloped lower portion 54
below portion
52 for holding the layer of pumice 30. Water 14 should be added to the pot to
about the
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top of the pumice layer, namely to the upper extent of the meshed portion 54.
The pumice
therefore draws water to the soil and root ball as in the earlier embodiments.
An
advantage of this embodiment is that the insert may be readily lifted out of
the pot to check
for the presence of water in the pot, and for the quantity or level of that
water. God results
have been achieved using commercially available containers used in the
hydroponic
industry. An alternate version of this embodiment shown in fig.4 illustrates
how numerous
smaller holes 44 may be spaced about the perimeter of the pot at about the
same level as
drain hole 40 (shown in fig.2) to avoid overfilling the pot. The smaller holes
should avoid
the need for a mesh therein.
The many advantages of the present system, as described earlier, may now be
better
appreciated. In particular, it is noted the water is delivered to the plant
continuously (as
indicated by arrows 36), via capillary action of the pumice rock. The root
ball 12 of the
plant draws water from the soil 32 in which it is growing, which in turn
causes the soil 32
to draw water up from the layer 26 of pumice 30 beneath. The pumice layer
supplies water
15 to the soil via the naturally occurring capillary mechanism of the pumice
material. A user
need only ensure that enough water is delivered on a periodic basis to keep
the pumice
wet, as noted earlier. A signal to provide more water is when the soil at the
top of the pot
starts drying out. The pumice layer also provides a "safety valve" regarding
over-watering
in that if too much water is provided (i.e. more than can be absorbed by the
pumice rock),
~p then the excess water will merely accumulate and sit in the bottom portion
26 of the pot,
away from the root ball 12. As the pumice then releases water to the soil, the
excess water
will be absorbed by the pumice rock for future release to the soil as required
by the plant.
Experience shows that, over time, some roots emerge from the root ball 12 and
do
grow into the pumice layer, but that such particular new root growth thrives
in the pumice
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layer and does not rot. Eventually (say, in about one year or so), as is the
case with many
growing plants, the plant 10 must be replanted into a bigger pot, preferably
using the same
pumice potting arrangement.
Experiments also indicate that improved plant health and/or growth may be
achieved by adding a slow-release fertilizer to the pumice rock after it has
preferably been
washed, as described earlier, to form a nutrient reservoir. The fertilizer is
delivered to the
plant as water is drawn up from the pumice rock. It is noted that in some
applications the
pumice need not be washed, particularly where harder varieties of pumice are
used.
The above description is intended in an illustrative rather than a restrictive
sense,
to and variations to the specific configurations described may be apparent to
skilled persons
in adapting the present invention to other specific applications. Such
variations are
intended to form part of the present invention insofar as they are within the
spirit and
scope of the claims below. For instance, the insert 50 with the pumice layer
30 may be
used in a larger hydroponic type setting, namely a number of inserts may be
placed in a
l~'ge pool of water (which is analogous to having a very large pot 20).
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