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AND POTTING AQUATIC PLANTS
you begin, gather your tools and supplies: Containers, dirt,
fertilizer, knife, digging tool, scissors, a hose (with a
handy shut-off) and of course - towels. If you do not have a
potting table or an area designated for the job, use a tarp
for a working surface. Choose a cool, shady area for
dividing and potting aquatic plants. Use damp newspaper or
sheets to cover bare plants to prevent the roots and/or
leaves from drying out.
Select squat pots wider than they are tall - they
accommodate the horizontal root structure of most aquatic
plants, and prevent plants (especially those taller
emergents) from tipping over. Sturdy black plastic tubs
are ideal. Consider plant size and shelf depth. If you are
using pots with drain holes in the bottom, use newpaper or
coffee filters to keep soil in the pot until it compacts.
Plants used for filtration in phyto- and bio-filters are
the exception. For these plants, use mesh pots filled with
pea gravel, not soil. This encourages roots to take up
nutrients from the water as it passes through.
aquatic plants perform the best when grown in heavy soils.
Use a chemical free heavy (clay) soil that does not have
added organics. Make a mix of 2/3 dirt and 1/3 sand - the
sand allows good root penetration and makes it easier for
repotting in the future. Do NOT use bagged potting soil -
it doesn't compact well, and peat, perlite, manure and
other materials float and foul the water. Leave at least
1" at the top of the pot for pea gravel or sand. The main
function of the soil is to hold plants in place and
provide trace elements as well as some nutrients. By
repotting, the new soil will increase the amount of
nutrients available to the plant. It also allows for
easier fertilization until the plant becomes rootbound
potted plants require fertilizer occasionally. For best
bloom, fertilize lotus and waterlilies monthly during the
growing season, twice as often during the hot months
(July/Aug.). Begin fertilizing when you see new plant
growth. Use a slow-release aquatic fertilizer which comes
in tablet form. Place the fertilizer well away from the
crown 1/2 to 2/3 of the way into the pot to prevent
burning the root. When potting new plants, put the
fertilizer near the bottom of the pot before adding more
soil and the new plant. Stop fertilizing in the fall when
water temps drop into the 60's (except for water
hawthornes and trop lilies you want to push for more
Gravel and/or Sand: These toppings help keep the soil
in the pot and prevent fish from mucking up the works as
they root in the pots. Be sure to avoid crushed limestone
or "road rock" in your pond.
& Marking Pen: It is a good idea to use a new
label whenever you pot a plant - include the name of the
plant and, for future reference, the date. Use a
waterproof marker and insert the tag deeply into the pot,
where it will stay and remain hidden.
WHEN??? TIMING IS EVERYTHING !
Early in the spring, before signs of growth, is the best
time to divide lotus. Start dividing waterlilies and most
other plants in spring as soon as there are signs of new
growth. Some, like Pickerel and Thalia, like to get some
good growth before being divided - wait until late May/early
June to divide these, and consider division every year. Wait
to divide Iris until late summer/early fall, so they can
store their energy to bloom early the next spring. If you
divide them in early spring, they will most likely not bloom
that same year.
aquatic plants are so resilient, most can be divided
throughout the growing season. Be sure to stop dividing in
late August/early September to allow the plants to 'root in'
before the cool weather sets in.
a general rule of thumb with marginal plants and submerged
aquatics, up-pot until you are satisfied with the pot size,
then consider dividing yearly.
PLACEMENT IN THE POND
Planting Depths for Aquatic Plants:
Place newly potted plants at shallow depths. Once
established, move them deeper as indicated below. Plants can
be set on blocks to live at their desired depths. The chart
below is for during the growing season.
The planting depths below are for during the
growing season, and are intended as a guideline.
Specific depths are listed for each plant in the Plant List
(available at Water's
Edge). See the list also for winter plant
care. As a general rule of thumb, never submerge more than
1/4 of the height of an emergent plant.
Plants & Smaller Lotus
- 2" - 6" (varies)
Planting Depths reflect the distance between the top of
the soil and the water surface.
hardy waterlilies anytime during the growing season- April
thru August. Waterlilies grow rapidly and some can even
fill their pot within a season!! Repot your waterlilies when
they have jumped their pot or when you can no longer find
space in the pot for fertilizer tabs. A
good size pot for waterlilies is 16" x 7".
Gather your tools and supplies.
- Fill the new container 1/2 to 3/4 full with your aquatic
- Place fertilizer tabs near the bottom of the pot.
- Use a Hori-Hori knife or trowel to dig the lily out of
its old pot.
- The growing crowns are the tips where new leaves and
buds emerge. Find two types of roots - thick anchor roots
and hairy feeder roots.
- Clean off most of the soil and cut away the old growth,
leaving enough rhisome (2-4") and roots to anchor itself
in its new pot.
- Place the cut end of the rhisome at the side of the pot
below the soil, with the crown pointing upward towards the
center of the pot at a 45 degree angle.
- Put 3-5 crowns in a 16 x 7 pan, for lots of blooms all
- Add aquatic mix to cover roots and most of the rhizome,
and top with sand or pea gravel.
sure the crown is well above soil and pea gravel.
- Gently lower
the lily into the pond.
lilies regularly throughout the growing season for good
AND SUBMERGED PLANTS
plants have a wide variety of growth habits - some grow from
rhizomes, others from a central crown, and still others with
running stems. In most cases, create a compacted mound of
soil about 2/3 the height of the pot. Place the plant on top
of the mound, spreading its roots across it. Cover the roots
and fill in the pot, gently compacting the soil.
rhizomes like Iris and Pickerel, and place the cut end
against the pot, with the growing end toward the center of
with central crowns or stem clusters, single stems, and
single crowns can be divided & placed alone or in
groups in the middle of the pot.
cuttings of runners on plants like Clovers & Pennywort
around the mound.
Take 4" stem
cuttings from plants like Parrot Feather & Veronica.
Place the cuttings half-buried in a full pot. Submerged
plants like Anacharis & Cabomba can also be divided in
marginals regularly throughout the growing season for good
bloom. DO NOT fertilize submerged aquatics. They take in
nutrients through their leaves.
lotus in the early spring, before there is any sign of new
are extremely vigorous growers. The larger sizes need to be
repotted every 2-3 years, and the bowl lotus once a year...
Their root structure is a running tuber which, when
confined, travels in circles around the inside of its pot.
Use BIG BROAD ROUND TUBS with NO
HOLES for your Lotus !
Use a pot 20-24" x 10-12" or larger for full size lotus.
- Use a pot 14-16" x 7-10" or larger for semi-dwarf.
a pot 8-12" x 5-7" or larger for the bowl lotus.
Pot sizes are important, due to the
running growing habit of the lotus, and please -
square pots - the growing end can get stuck in the
Gather your tools and supplies.
- Put 1" of sand on the bottom of the new container and
fill 1/2 to 3/4 full with your aquatic mix.
- Take the lotus out of the pond and carefully dump the
dirt/root mass out of the pot, upside down onto a tarp.
Growing ends of the lotus protect themselves from winter
damage by diving to the bottom of the pot. The best tubers
will be found wrapped around the bottom.
wash the soil off of the tubers and unwind them,
discarding the dark and/or mushy ones as you go.
life of the lotus is in the growing ends - take care not
to damage or bruise them!
As you expose them, you will see sausage-like tubers,
linked together. The "links" are called internodes. . .
the nodes are the constrictions between them. New growing
ends, leaves and flowers emerge from the nodes.
through the internodes to make sections that include one
or more growing ends (a sausage-and-a-half each). Float
these in a tray of water until you are finished dividing.
the soil in the container, making it muddy but not soupy.
Select one or two of your best divisions and make a
shallow horizontal trench for each. Gently lay them in
with growing ends pointing up. Cover the thickest part of
the tuber with 1-2" of soil. Top all with 1" of sand.
Gently saturate the container and lower the lotus into
NOT fertilize lotus until it has standing leaves (late
May). Thereafter, fertilize your lotus regularly
throughout the growing season. For best bloom, fertilize
twice as often during the hotter months - July and August.
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