When I repot in the spring, I use pots without holes, (or you can line pots with black garbage bags) and throw in about a half cup of Osmocote Pellets (Veggie Formula) per 18" pot on the bottom of the pot before I add the soil (I use compost...
composted cow manure works best for me).
Osmocote is a micro-coated fertilizer, using the osmosis process in conjunction with the temperature, the nutrients inside the micro-coated pellet pass through the micro-coat, the warmer the temps, the faster it is released. This corresponds to the lilies (or lotus, or any pond plants) needs for nutrition. As it warms up from Spring to Summer, your plants grows faster, needs more nutrition...more food. Osmocote can NOT dissolve all at once like fertilizer tabs or spikes can, so it is virtually impossible to burn your plants with Osmocote (unless you don't follow directions and dump WAYYYY too much of it in the pot). There is a chart on each container of Osmocote that tells you how much to use per diameter pot.
Fool proof I say...but they are famous last words aren't they.
Common sense comes into play here too.
Think about what water lilies grow in, in their natural habitat, at the bottom of a natural pond.
Do they grow in sand?
Do they grow in Kitty Litter?
Do they grow in Gravel?
Do they grow in topsoil?
Do they grow in coco fiber?
Do they grow in clay?
'NOPE' to all of the above.
Water lilies grow in the composting, rotting muck at the bottom of natural ponds. (It stinks.) This muck is a combo of dead plants, dead animals, dead insects, and all the other organic debris that naturally gets into a pond and settles out onto a layer of sediment on the bottom. TONS of micronutrients in this muck too, not to mention beneficial bacteria, and yes, anaerobic bacteria, which causes most of the stench. There are no 'holes' in the bottom of natural ponds. No need for holes in pots either. Lilies LOVE to grow in this rooting, stinky quagmire.
Another good aspect to pots without holes is that the nutrients and fertilizer has to seep upwards into the water lily roots (or any pond plant roots) and can not leach out through the bottom holes. This way your lily gets
ALL the nutrition.
If you use pots with holes, the fertilizer (and soil nutrients) leach out and will cause algae blooms.
And lilies in nature have no 'holes' in the bottom of mud ponds. They don't mind stinky, anaerobic conditions.
Their roots don't get deep enough to go into the completely anaerobic environment.
This is why pots that are wider than deep are the best...because lily roots do not get too deep, but grow laterally through the richest, most nutrient laden layer of pond settlement.
So by planting your lilies in compost, it's the next best thing to what your lily really wants...natural pond muck!
And by adding Osmocote, you can have at least 4 months of gradually released supplemental nutrition for your lilies, and all pond plants.
And you wont get any fertilizer burn.
But you will get bigger lilies, more blooms, multiple daily blooms (instead of one at a time) than you've ever had, and have a lot less maintenance!
(not to mention Osmocote saves you money in the long run)
And each bag of Osmocote has a graph showing you the ratio of pot size to fertilizer dose.
The only way you can screw it up is if you can't read and/or follow directions.
And another copy/paste from another topic:
Here is another 'secret' I use: I stick a small walnut sized wad of plain steel wool on the bottom of my pot....keeps the lily (or any plant) from getting chloritic. (yellowing from lack of iron)
Also, I mix Mosquito Quick Kill granules (it's all natural, uses Bacillus thurengensis aka BT) into my Compost. It innoculates the soil with BT, killing the caterpillars that eat your lily leaves, and it will of course kill mosquitos. Completely fish safe, pet safe, human safe since it uses a bacteria that gets into the bugs digestive system, disrupts it and causes the caterpillars (and mosquito larvae) to starve to death.
When mixed into the soil, it seems to 'time release' and last all summer.
I mulch the top of my potting mix with a layer of pea gravel, and then if it's going into a koi pond,
I'll place larger fist sized rocks on top of the pea gravel, fitted together like puzzle pieces yet kept away from the crown of the plant so it can grow.
Broken up flagstones fitted together work GREAT for this top 'koi proof' layer.
Pondly...Joyce
PS: One word of warning, if you buy composted cow manure, it should look and smell like high quality compost...it should not smell like COW POOP!
It should smell just like rich potting soil, similar to that greenhouse smell that all of us gardeners love so much.
It should not be moldy, stinky, or nasty in any way.
If you do open a bag and it's nasty, funky, stinky.....cultivate your common sense and DON'T use it!
LIKE ANY GOURMET RECIPE...CHANGING THIS RECIPE IN ANY WAY WILL NOT GET THE SAME RESULTS!So don't come on here in a couple months blaming me for your failure if you haven't followed the recipe to a tee.