Pond Plant Fertilizers

[NancyMc]

I have looked back in the archives and found only one post on what to use for pond plant fertilizing. I have always used Laguna slow release fertilizer spikes but I don't think they work very well and cost a bundle. When I took my lilies out of the pond this year and broke a stick open, there was still a lot of "stuff" still in them. What does everyone else use? The one post suggested using rose stakes and breaking them in to pieces. My concern is that if I use a lot of fertilizer it will cause heavy algae growth in the pond but that may be incorrect?

 

[Waterbug]

I like tree fertilizer spikes. You do have to hit them with a hammer to break into chunks imo. About 1/3 the cost of rose spikes and such. I put about 3 chunks (3/4 of a stick total) in a 15 gal pot for Canna. I never grew lilies very much so don't know about those. You can get tree, fruit tree and evergreen spikes which have different ratios. Most places that sell fertilizers sell these but you have to hunt around.

Whether fertilizer causes algae growth depends on other factors and the kind of algae. It certainly can. Many, many posts in pond forums warning on the dangers of nutrients and algae. But imo it's a bit more complicated. One thing you can do is test your water for ammonia, nitrate and phosphorous. In many clear ponds these number are well above zero yet the pond stays clear and string algae (macro algae) isn't taking over the pond either although is generally present. IMO if these nutrients aren't currently zero it means that isn't the limiting algae factor and add more shouldn't increase algae growth to a great degree. Bottom line is most water gardens produce a great deal of nutrients even without fertilizer.

However, should whatever is limiting algae go away it could then use the added nutrients to grow more. To my way of thinking if a pond goes green or string algae grows fast the added nutrients are only going to make the water greener or the string algae grow a little faster. I still have to deal with the green water or the string algae, doesn't really matter that it's 10% or 20% worst. So to me the added fertilizer isn't the end of the world. I'd rather have the plants doing well...algae can be dealt with.

Adding fertilizer to the vegetable garden is the same deal...weeds grow a little faster and more of them...so I pull them out. I have to pull 20% more weeds, no big deal. Pulling 20% fewer weeds and a low harvest is a deal breaker.

 

[j.w]

Tomato spikes and Osmocote mixed in the soil work well also for water lilies.

 

[RoyalFeather]

Are these safw for use with fish? They are all good ideas, but just wonder.

 

[Waterbug]

As safe as fertilizer can be.

 

[addy1]

I use osmocote under the kitty litter clay, also add an occasional fertilizer tab. I have not had any algae issues or bothered the fish with the fertilizers

 

[Fishylove]

i do the same as addy, but I use granuals, put it under the litter before you put it back in the pond. Pots I cant remove I use tabs. If you use the granduals, it should say on the bag if it is safe for fish and wildlife.

 

[j.w]

They never bothered my fish.

 

[Craig58]

We use tablets in our lillies and lotus. Similar to this: http://www.stillwatersnursery.com/pondproducts/pondfertilizer.php

But really, any tablet will do. They are all primarily the same thing.

What we found works well is this:
Get a PVC pipe that the tablet will slide down into. Usually a half-inch schedule 40 PVC works, about 12" long works well.
Get a second PVC pipe that will slide down into the first. 1/2 CPVC pipe works nicely in the 1/2 inch schedule 40. This should be longer, 18" is good.
Push the larger PVC pipe down into the pot about 3-4". Can be tough sometimes.
Drop the tablet down into the tube.
Drop the smaller 1/2 pipe down on top of the pond tab.
Now, as you hold the smaller pipe down against the pond tab, slide the larger pipe up and off the smaller pipe.
Push in the soil/gravel around the smaller pipe.
Pull the smaller pipe out and push in more soil/gravel into the hole.
The pond tab should now be buried about 3" into the pot.
This is great for mid season fertilizing and can be done without pulling the pots out of the pond even. Most of the time as you pull the smaller pipe out, the soil and gravel will just back fill by itself without any help.

This helps ensure the fertlizer stays with the plant! Takes a couple practices but once you do 2 or 3, you'll be able to do pots 2-3 feet out in the pond.

Craig

 

[addy1]

Neat idea craig, problem is my lilies fill the pot up with roots darn fast. Have to dig around to find a spot to put a tab in. I may go for larger pots for a few of them.

 

[Craig58]

Yeah Addy. that's part of the problem of inserting the first pipe as the season goes on. But i've found you can chop a bunch of roots like that with little problem to the plant.

Craig

 

[addy1]

They are tough plants, I don't baby them at all. I need to purge some again, had solid lily cover this last summer.