Saturday, February 19, 2011

Mid-February Monarch Butterflies in Phoenix

Male monarch at Rio Salado
The monarch butterflies at Rio Salado are showing their age. Wings are fading with tiny tunnels of scales missing. But they are busy flying when it's warm, sunning when it's cool, and nectaring. In fact the males set up active patrols this last week over the milkweed for the first time this Spring. We know for sure at least three monarchs survived the last deep freeze at the beginning of February, but there may be more. Seep Willow continues to be a favorite nectar source, but freeze damage to the largest stand is pushing monarchs, queens, snouts, and others to seek out other plants along the creek. Fortunately many are in bloom throughout the area and a few buds are appearing on Sweetbush, Bebbia juncea, too, a delight for visiting butterflies.

Tatsuyo's monarch larva
Rio Salado isn't the only place with monarchs these days. Tatsuyo on South Mountain emailed me this week with her surprise - a few monarch caterpillars in the milkweed she was cutting back! These caterpillars survived the deep freeze of early February without any protection of any kind. It makes me wonder about any other survivors in niches around the greater Phoenix area. Of course, there needs to be milkweed present to have this kind of find. It gives a whole new perspective to what an overwintering monarch can look like. We do know that the monarch butterflies stayed longer than usual with our warm November and December. Time will tell if this is just an oddity this year or a regular event. Luckily, Tatsuyo does have more milkweed available to feed this hungry caterpillar.

Arizona Milkweed,  Asclepias angustifolia
While its still too early to prune heavy frost damage, it is time to get ready for spring migrating monarchs which make their first appearance mid-March. This is the perfect time to start milkweed seeds if you haven't already. You can find seed sources at: Bring Back the Monarchs. My favorite place is Butterfly Encounters in California. It is also very easy to harvest milkweed seed and grow it yourself. The advantage is that you know this particular local variation of the seed type is accustomed to the Sonoran Desert. Milkweeds to consider that are native are Asclepias subulata, Asclepias linaria, Asclepias angustifolia and the non-native Aslcepias curassavica. If you grow a non-native, be sure to also plant natives. In our deep freezes this winter many non-natives perished, but the natives thrived. In fact, Asclepias angustifolia is already putting out fresh, lush, new growth - a favorite for monarchs to lay eggs.

Asclepias curassavica in seed trays
 Growing milkweed from seeds is easy. You can buy trays with pellets that are easy to use. Soak the pellets in warm warm water until they expand and plant your seeds. I usually add three seeds per pellet. These seedlings were started on January 20th, almost a month ago and they are ready for transplanting.

Seedling roots ready to plant
Potted Asclepias subulata seedlings
When the seedling roots begin to grow through the pot they are reading for transplanting. This week I was busy transplanting Asclepias subulata in large pots for my yard. I find plastic or ceramic pots better since they are easy to move into the sun or shade as needed - and to protect larvae from predators. I also plant milkweed in the ground, but recommend waiting until the soil warms more for rapid growth. If your seedlings are as over run with roots as my sample above, plant it in a small pot for now. Within two to three weeks the soil should warm - keep an watchful eye on temperatures. (Notice how lush Asclepias subulata seedlings are when they are young versus the coarser stems we are more used to seeing.)

You can also easily start your milkweed seeds directly in a pot and place it in a sunny window. For pots I tend to use the moisture control plant mixtures to help prevent rapid evaporation during our hot summers. Remember indoor winter air is extremely dry, too. Add a layer of seedling mix on the top for easy germination. I also mix some of seedling soil mix to the moisture control mixture in the lower portion of the pot. The upper layers dry out more rapidly than the lower with the air exposure and I want to prevent root rot in the deeper depths. I also plant thickly for abundant lush growth for hungry caterpillars.

New growth on Asclepias curassavica
Most of the Tropical Milkweed or Bloodflower, Asclepias curassavica, in the garden died  in our deep freeze. Out of eight, only two plants are showing new growth at the soil line so far. Potted plants were able to survive since they were easily moved to a warmer location. If you haven't already, be sure to cut A. curassavica back for lusher and thicker growth. This also prevents diseases that could survive on plant leaves over the winter that could harm the monarchs or queens who visit your yard. This plant was cut back just two weeks ago and already you can see the new growth. Lightly fertilize with a half-strength fertilizer solution to help this process. Potted plants often need supplements due to frequent watering.

Enjoy the changing weather this weekend - hope we get some much needed rain!

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