Milkweed as tall as I am

[Marina]

I have a large yard with about over hundred or so milkweed plants. with new ones coming up every day. We live on the Texas-Mexico border so the climate is warm and we have milkweed all year.

I usually leave it alone and let the cats have at it, but this year it's gotten really tall. Its almost as tall as I am. about 5 1/2 feet! It's very healthy and very full, but um very tall. I was going to cut it back today after church, however I ended up entertaining some guests. About 75 or more monarchs we're drinking (and mating )up a storm. I'd never seen so many (and never knew they could stay together so long).

So I guess I'll leave it alone and check for eggs tomorrow, but does everyones butterfly weed get this tall? How often do you cut it back? how tall will it get if I leave alone?

[monarchmama]

It seems to me that the older a milkweed plant is, the taller it gets each year and the thicker and woodier the stems get . When I first started raising milkweed from seed it was comparitively short the first year, and each successive year the plants seem to get taller and the leaves bigger.
This year's weather conditions in the East has been condusive to milkweed growing, as we have gotten plenty of rain and lots of sunshine. My common milkweed that is about five years old is 6 to 6 1/2 ft this year, the tallest it has ever been. The 2nd and 3rd year swamp milkweed is 5 to 5 1/2 ft tall which is the tallest I have ever seen it.
I do think alot has to do with the weather because all of my flowers are thriving . Most all of my summer perrenials are so tall and so full that they are taking over the pathways and the 24" -36" plants are more like 36 - 48" plants this year. I joke about my "jungle" because I have to keep trimming things back just to walk the path and to let my smaller plants get sunshine.

I have done the same with the milkweed, cutting a third of my plants half of the way back every two or three weeks. I am am experimenting with this, as most summers I am running low on milkweed just when the larvae need it the most. New growth comes on very fast, as milkweed is very opportunistic once it gets established. It seems to be working as I trim up my patch every two or three weeks cutting off dead flowers before it goes to seed, and cutting back larger plants back close to the ground once it gets too old and dry to be of any use as larvae food. A good way to tell is when the mama butterflies stop laying eggs on it it is safe to cut back. I think they must have some way of sensing the quality and moisture content of the milkweed as they are laying eggs as I have never found an egg on an old leather leaf, and the majority of eggs are laid on the more tender of the leaves first. When I cut these older plants back this far before they produce seed pods, they send out multiple tender young sucker shoots just right for feeding first and second instars. I try to leave the flower heads for as long as possible, as the honey bees and monarchs are flocking to it for nectar, but cutting them back before the seeds pods form forces it to make new leaves and blossoms. It is basically the same as deadheading any flowering plant.
I do leave the last batch of flowers in the fall go into pods so that I have seed to share and start new plants with.