You can only briefly delay their emergence by refrigerating them. If I were in your situation, I would go ahead and let the caterpillars pupate and keep them in a warm, light area so that they will eclose as soon as possible. And I would release them on a warm day and hope they would travel south.

You can keep the pupae cooler than normal, but not too cold, to slow down the process. However, if you do so, you may run the risk of having them eclose during colder weather.

Monarchs will not live through the winter as pupae. They also won't survive as adults if they are not in their overwintering colonies.

Good luck!

Sandy

Thanks for your response, Sandy. I have brought them indoors and they are getting very active. The teacher brought me a handful of Tropical Milkweed stems for the cats to feed on and they are eating and crawling around.

Texas weather is very unpredictable this time of year - maybe we'll have a few warm days in a row and the butterflies will be able to make it to South Texas and beyond. We have a hard freeze coming this weekend up in North Texas, but there still may be flowers south of here for them. Fingers crossed!

I am in the Houston area and I still have lots of nectar flowers and shrubs for the butterflies. The spring and summer were so disappointing, but the fall sure has made up for the lack of butterflies. I had bushy milkweed plants, about 38 of them, until about a week ago: the cats have just exploded in numbers! My plants are just stripped of all the leaves!! Yah! Finally! I have released about 35 monarchs in the last month or so, which isn't really a large number, but considering how bad this year was early on, it is amazing.

My mexican sunflowers went nuts this year and reseeded themselves. I had about 500 plants come up in one of the front beds and still have new seedlings coming up and blooming while very small in size. I really think that they did this so there would be plentiful nectar for the monarchs as they travel to Mexico. I have had so much butterfly traffic that it has certainly made up for the slow start this year.

Mechelle

Well Mechelle, I hope my four Monarchs can make it down there to enjoy your garden!

My garden here in Bedford is also very beautiful now. Ever since late September it has just burst forth with flowers. I felt like the flowers were saying thanks to me for babying them all through the summer. Most butterflies left by Halloween, but I've had lots of other insects around to entertain me. All will come to an end this weekend as we're expecting our first hard freeze.

I had collected 29 monarch cats before our first freeze & now have released at least 8 since they eclosed...I have them outside because several of them pupated on the outside of my box. It is going down to the low 20's on Monday so will bring them back inside the house. I had released a few when the temps were in the low 50s & they just hung onto the flowers I put them on for several days. Not sure if any others will make it to eclose but will release them if they do. I also had late PVST cats on my pipevines. Only half made it to pupation. They will overwinter as crysalids.
This has been a strange butterfly year here west of DFW for me! I am out of milkweed since we have had several frosts before our first freeze. It seems colder here earlier than we have ever seen in the past 10 years. It has never gotten down to the low 20s until February!
Luck to us both for these late Monarchs!!!

Hi, I wanted to pass this along to anyone in the Dallas area.
I have Monarch cats, and I was searching for some place to take them.

With the freeze, I have been afraid to release them since I am not sure they can find enough flowers to make their way.

I am taking mine to the Texas Discovery Gardens in Fair Park, Dallas Texas. They have a climate controlled place to raise them.
This was suggested to me by my local Master Gardener program.

You can reach Texas Discovery Gardens butterfly center here:
214-428-7476 ext. 341

Hope this helps others.

EG