I think i know why your pickerel plants, occasionally, rot by overwintering them in the deep water.


1. you may be trimming the leaves off while they would have had a few more weeks of limited sunlight absorption.

2. you may be cutting the leaves to close to the bulb

3. you might want to not cut any of the more fresh leaves at all

4. most importantly: I suspect that they are NOT rotting over winter - in fact, they are doing great over winter, perhaps. They are rotting in the spring. perhaps, you are taking them up from the bottom too late - days or weeks too late. Especially, since you have them in freshly activated bacteria rich soil.

Maybe you should remove them from the soil [do you?] and clean off the soil from the roots - this may greately increase the survival. And maybe take them to the 12" a little earlier then usual.

This is how we can know if my theory is correct: when you obeserve[d] that the bulbs are mushy and rotten:

1. is it only in the spring that you discover this, or do you discover this midd winter?

2. are there enough examples of only partially or "starting to" rot bulbs and tubers that you find in the spring, when you're ready to take them up? if so, i'd imagine that the rot must be beginning not to long before you've taken them up, in late winter/early spring. have you noticed in years when you've removed them later that there are more losses then in years you removed them earlier and have you noticed that they tend to mostly be partially or beggining to rot?

i'm very much hoping that this is the problem... which is avoidable

"1. you may be trimming the leaves off while they would have had a few more weeks of limited sunlight absorption."

I usually don't cut them off until they rot but sometimes sooner. I doubt this is much of a factor.

"2. you may be cutting the leaves to close to the bulb."

I cut all my marginals above the water line which means 1 to 3" above the top of the pot.

"3. you might want to not cut any of the more fresh leaves at all"

By the time I trim, I don't really have "fresh" leaves (I assume you mean new green ones). I do leave such leaves on my iris as they have a little growth in the fall.

"4. most importantly: I suspect that they are NOT rotting over winter - in fact, they are doing great over winter, perhaps. They are rotting in the spring. perhaps, you are taking them up from the bottom too late - days or weeks too late. Especially, since you have them in freshly activated bacteria rich soil."

As I said, I do not move them to the bottom of the pond. This year, I moved one a few inches deeper but not much. I usually don't move the pickerel weed at all. For a few years, one plant may do fine in a location and then doesn't come back at all the second or third spring that's it's there. Some die the first winter. My old clay soil has bacteria all year so it's not really freshly activated in spring. It's mostly below the freeze line and in near zero oxygen conditions in the bottom of the pots. When one plant dies, I do not see any spring growth at all so I know they're dying over winter. The plants only have a few inches over the top of the pot.

"Maybe you should remove them from the soil [do you?] and clean off the soil from the roots - this may greately increase the survival. And maybe take them to the 12" a little earlier then usual."

I do not remove them from the pots. The tubers I've seen when repotting are always mushy and not hard like other plants. As I said, the plants are always only a few inches over the top of the pot. I have never put them with a foot over the pot.

"This is how we can know if my theory is correct: when you obeserve[d] that the bulbs are mushy and rotten:

1. is it only in the spring that you discover this, or do you discover this midd winter?"

I see this when dumping out a dead pot that never came back in spring. I always give it a few extra months in case it will come back. They do come up later than some other marginals. The tubers I dump are mushy and stinky. The few times I've repotted living plants, the tubers didn't stink but weren't very hard either. Almost not like a tuber at all but a regular perennial.

"2. are there enough examples of only partially or "starting to" rot bulbs and tubers that you find in the spring, when you're ready to take them up? if so, i'd imagine that the rot must be beginning not to long before you've taken them up, in late winter/early spring. have you noticed in years when you've removed them later that there are more losses then in years you removed them earlier and have you noticed that they tend to mostly be partially or beggining to rot?"

As I said, I do NOT move them. This is all therefore irrelevant. I have so many plants that I don't really examine the pots nor can I remember what's in half of them! If a pot doesn't put anything out by early summer, I dump it. You seem to be under the impression that I either have a ton of pickerel weeds or that most die in the winter. In fact, at most, I've had two pots any one year. I've bought maybe a dozen of them over the years, mostly more "white" ones that always bloomed purple. Today, I have just one living that I got this year. Sometimes they live over the winter and sometimes not. Last summer 2003, I had two pots that had lived a few years straight but they didn't come back this spring despite being in good condition in the fall. If I had the room, I could lower the plant but since there is no guarantee at any location, I don't bother because they sometimes do make it. Anyway, I don't have any time!

interesting - man, i wish i could figure out why this happens to your pickerels. The point of my concern is this.

Around next years (now, i know for sure:) 18" X 13" pond, I'm going to have a 6" deep first marginal shelf which is 18" wide [must of the will be rocks toward the edge descending from 0"-6" and I'm going to completely fill that 3/5 of that marginal area circumfr., as well as a few spots in the following marginal shelf at 12" depth, with pickerel plants, arrowheads, and blue-flag iris, as well as a few others. That's a lot of plants, not to mention making a soil filled bog behind the pond with those plants. So, ideally, I will find out the best way to overwinter these, or conclude, i hope, that only about 1/3 will die over the winter and i can count on the rest making it by either leaving them in the 6" first shelf (doubt it!) or easily lowering them to the 18" and 24" depths.

I'd hate to stock all that area and loose everything but the extremely hardy irises and forgetmenots.

I don't know how it will turn out until it's been done. There are too many variables I think. Like I said, I've had many plants survive freezing so I'm sure you'll still have plenty for the following spring. There seem to be some plants I can never get to live (even a few months, not even getting up to overwintering) such as water clovers and marsh marigolds. In your pond, you'll soon find out which plants do great, ok, and not good. Over time, you just stick with the ones that work for your situation.