Monarchs want YOU to plant milkweed: Butterfly-friendly plants for sale at HMNS

The butterflies need your help! With urbanization, and a host of other factors, monarch butterflies are at risk of not finding places to lay their eggs. So why not help while improving the butterfly traffic through your garden with a butterfly-seducing plant from our biannual plant sale?

Milkweed plants in the genus Asclepias are extremely important for butterflies, especially monarchs. While the blooms provide copious amounts of nectar for many different butterflies, the foliage is an essential part of the monarch butterfly’s life cycle. Milkweeds are the only plant monarch caterpillars will eat. In other words, they can’t live without it!

Native milkweed plants grow along roadsides and in open fields. The butterflies find them by honing in on their volatile chemicals and finally locate the exact plant by “tasting” nearby plants with special receptors called chemoreceptors on their feet. Once a gravid female (one who has mated and is ready to lay eggs) finds a good milkweed plant, she will lay eggs on it — and the miraculous process of metamorphosis has begun!

There are about 100 species of Asclepias in the United States, and over 30 in Texas — but monarchs seem to prefer some of them over others. According to a study by Linda S. Rayor, described in The Monarch Butterfly: Biology and Conservation, when given a choice, monarchs prefer to lay eggs on other species of milkweed over the native species Asclepias tuberosa.

Butterfly - Tropical Milkweed

Besides being a host plant for Monarch larvae, Tropical Milkweed (A. curassavica) is a great nectar source for many butterfly species!

Why? Different Asclepias species contain different cardenolide concentrations (cardenolides are the chemicals in the milkweed leaves that taste bitter). As they eat, the caterpillars store these toxic chemicals in their bodies and thus become distasteful to their predators. A. tuberosa has been found to contain low amounts of cardenolides compared to most other species of milkweed. Although it is unclear how monarchs “know” this, they do not usually use A. tuberosa as a host plant.

Several other native milkweed species, however, are great host plants for the monarch. Asclepias asperula (Antelope Horns), A. viridis (Green Milkweed), A. incarnata (Swamp Milkweed) and A. oenotheroides (Zizotes Milkweed) are some of the more commonly found milkweed plants in our area that monarchs use as host plants.

Unfortunately, most of the native milkweeds are hard to find in plant nurseries. One reason is that their seeds require moist stratification to germinate, and even with this pretreatment, germination can be splotchy. Furthermore, young plants of A. asperula, viridis and oenotheroides take several seasons to establish their thick taproots, and can be hard to transplant.

On the bright side, most of the native milkweeds, except for A. incarnata, are drought tolerant and can handle being mowed. Swamp milkweed obviously likes moist soil. All milkweeds grow best in full sun.

Butterfly - Green Milkweed

Asclepias viridis, Green Milkweed

Most gardeners are familiar with tropical milkweed, or Asclepias curassavica. This plant is commonly available in local plant nurseries and attracts butterflies like a magnet! Its bright orange and gold flowers are irresistible to many butterflies, and the high levels of cardenolides in its foliage make it especially sought out by female monarchs looking for a place to lay their eggs. Although it originates in more tropical climes, it is relatively cold hardy and will usually come back from the base of the plant after a freeze. It is also easy to propagate from seed, and in fact will sometimes seed out (make more of itself) in a garden.

So tropical milkweed seems like the ideal plant. However, one issue with this species is that it is not native to our area and does not exhibit the same characteristics of our native milkweeds, all of which die back to the ground in winter. This perennial habit seems advantageous, but it can be a problem for a couple of reasons. Because it has leaves year-round, it may encourage monarchs to overwinter locally instead of migrating to Mexico. It can serve as a host for a disease that affects monarchs, called Ophryocystis elektroscirrha, or simply O.e. This disease is caused by a protozoan parasite and is spread in the dormant stage of its lifecycle as a tiny spore.

These spores are typically on the abdomen of an infected monarch butterfly and can be spread to her eggs or onto the milkweed plants themselves when a female lays eggs. Then, when the caterpillars hatch out of the eggs, they consume the spores that lie on their empty egg shells or on the leaves around the egg and become infected.

Over a few generations, the parasite load can build up to high enough levels that it impacts the butterfly’s survival. Depending on the severity of the infection, the disease can make the caterpillars look a bit grayish and their stripes not as distinct. When the caterpillars pupate, their chrysalis may look brownish or spotted. The butterfly inside may emerge but have problems, such as an enlarged, gray abdomen and weak, faded wings.

Sometimes they emerge and look healthy, but secretly harbor O.e. spores on their abdomens. Other times they don’t emerge from the chrysalis at all, or get stuck while trying to come out.

So what is my point? I thought we were talking about milkweed plants! ;-) The reason this is important is because O.e. spores persist on the leaves of the tropical milkweed plants, waiting for an unsuspecting caterpillar to munch them up. To break this cycle, we recommend cutting your tropical milkweed plants back after a monarch generation has stripped their leaves, especially in the spring and fall. A simple pruning of the plant’s stems about six inches from the ground will get rid of any remaining spores and will sprout new growth in no time.

Some other closely related plants that monarchs will use as a host are Gomphocarpus physocarpus or “family jewels” milkweed, and a species of Funastrum or twinevine. Gomphocarpus is a lot like A. curassavica in that it doesn’t lose its leaves in the winter so it also needs to be cut back periodically to keep it from spreading O.e.

Butterfly - Funastrum cynanchoidies flower

Funastrum cynanchoidies flower

Funastrum or twinevine is an interesting climbing plant native to south Texas and Mexico. The plant is not very impressive looking until the summer, when it puts on beautiful balls of milkweed-like flowers that are great nectar sources for many kinds of butterfly. Another good thing about it is that when monarch caterpillars have stripped all your milkweed plants of their leaves and are still hungry, they will eat the leaves of Funastrum.

With their habitat dwindling due to urbanization, the use of Round Up ready crops, shrinking right-of-ways due to intensive agricultural practices and other factors, monarch butterflies need all the help they can get. The take-home message today is PLANT MORE MILKWEED! (please)

For milkweed and other awesome butterfly host and nectar plants, come visit us at our biannual Spring Plant Sale on Saturday, April 5th from 9 a.m. until we sell out! We are located on the 7th level of the Museum parking garage. Parking is free if you spend $30 or more!

Come early, the plants go fast!

Get your garden going with our Semi-Annual Plant Sale this Saturday!

Do you wish you had a butterfly garden? Would you like to attract more of those beautiful creatures to your pre-existing garden? If so, don’t miss our Spring Plant Sale, Saturday, April 6th from 9 a.m. to noon! It takes place on the seventh level of the HMNS parking garage, where we will have a plethora of butterfly plants to choose from.

Of the dozens available, I chose 10 of my favorites for spring:

1. Zexmenia hispida or Hairy Wedelia. This perennial bush grows up to 2 feet tall. Native to the Texas Hill Country, it likes full sun and is drought-tolerant. The 1-inch wide yellow flowers cover this bush from spring through fall. It is a great nectar plant! Because it dies back in the winter, it needs a good haircut in the spring. We have this plant growing in our Demonstration Garden outside the Cockrell Butterfly Center. Stop by and check it out!

Get your garden going at our Spring Plant Sale: Saturday, April 62. Gaillardia pulchella or Mexican Blanket. If you like native plants, this is a must have! You will have flowers on this plant from spring to fall. The blooms resemble targets that literally direct the butterflies to the nectar within! These plants typically grow in a mounding clump, with the flowering stalks reaching up to 2 feet tall. They like full sun and have average to low water needs once established. Save the seed heads and re-plant in spring!

Get your garden going at our Spring Plant Sale: Saturday, April 63. Red Porter Weed (Stachytarpheta sp.). This tropical plant attracts butterflies and hummingbirds with its red spiked blooms. It’s a tender perennial, but it usually comes back from the base of the plant in spring if it is well-mulched in cold weather. It likes full sun and average watering, and grows up to 3 feet tall. We use these plants in the Butterfly Center year-round to keep our butterflies fed and happy!

Get your garden going at our Spring Plant Sale: Saturday, April 64. Lantana montevidensis or Purple Trailing Lantana. This spreading perennial grows up to 2 or 3 feet wide, and blooms nearly year-round! It likes full sun but can tolerate a little bit of shade, especially in the afternoon, and has average to low water needs. The specimen in our Demonstration Garden has started to outgrow its space after a few years, so cutting it back once a year is recommended.

5. Stokesia laevis or Purple Stokes Aster. The flowers on this plant are striking! Up to 3 inches wide, they are a beautiful purple color with white centers. This herbaceous perennial only grows to about a foot high and is drought-tolerant. It blooms from spring through summer and is also a great plant for bees (we need to feed them too)!

6. Tithonia rotundifolia or Mexican Sunflower. This hard-to-find annual likes full sun and has average water needs. The plant tends to fall over and grow up from the stalk into a medium-sized bush — about 3 by 3 feet. You can save the seeds as the flower heads turn completely brown and dry up. Its one of the best nectar plants for butterflies!

Get your garden going at our Spring Plant Sale: Saturday, April 67. Asclepias physocarpa or Family Jewels Milkweed. This plant has a funny name but is a seriously good host plant for Monarch and Queen caterpillars. Similar to Asclepias curassavicaI, or Tropical Milkweed, this species grows taller — about 4 feet — and has pinkish-white flowers. It likes some light shade in the afternoon and has average water needs once established. The seed pods that develop give rise to their common name, “Family Jewels.” Grow one to see what I mean!

Get your garden going at our Spring Plant Sale: Saturday, April 68. Cassia alata or Candlestick Cassia. A fast growing, tender perennial tree, this is a host plant for Sulfur butterflies — those bright yellow ones! This plant grows up to 8 feet in one year, so you will need some space for it unless you cut it back occasionally. It likes full sun and average watering. Blooming late spring through fall, the large yellow flower spikes top off the tree. The well-camouflaged Sulphur caterpillars can be found on the newer growth or the flowers. The caterpillars eating the leaves are usually green striped, but those that eat the flowers tend to be more yellow. It’s always a treat to find them!

9. Foeniculum vulgare or Bronze Fennel. We usually think of fennel’s culinary use, but it is also a butterfly host plant. Have you ever noticed those green, black and white striped caterpillars in your herb garden? They are the larvae of the gorgeous Black Swallowtail butterfly! They like to munch on almost anything in the Apiaceae or Celery family, including fennel, parsley, dill, even carrot leaves. They will also eat another herb, rue, which is related to citrus. Bronze fennel is my favorite host plant for the Black Swallowtail. The plant forms a purplish feathery cloud, which looks striking in the landscape. Bronze fennel can grow to be a 2 to 3-foot mounding shrub and can even last as a perennial. In full sun, it grows more compact and gives off a licorice smell. It has average to low water needs once established. An unusual and versatile plant!

10. Passiflora foetida or Love-In-A-Mist Passion Flower. Passion vines are host plants for our native longwing — the Gulf Fritillary. However, some passion vines are not as favored by the caterpillars as others. The best ones for the Gulf Fritillary larvae are Incense (a hybrid), blue passion flower (Passiflora caerulea), native passion vine (P. incarnata) and P. foetida. Of these, foetida is my favorite. Its fuzzy leaves give off a “skunky” odor — hence the species name “foetida,” meaning “fetid.” The common name, Love-In-A-Mist, comes from the way the lacy sepals (Google it) cover the bright red fruits, like love in a misty shroud. The delicate pink blooms occur in clusters — which is somewhat unusual for passion flowers — and smell a little bit like bubblegum. In my experience, this vine does not grow out of control like some others, but occasionally sprigs will pop up in random places in the garden. Just pull them up when they grow in undesired locations. This plant likes a little bit of shade and average watering.

Get your garden going at our Spring Plant Sale: Saturday, April 6Well, that’s the line-up! I encourage anyone who has a hankering for butterflies to visit our plant sale, even if it’s just for advice. There will be many experts available to help with questions, so feel free to ask. Come early though, as the plants don’t last for long, and bring a wagon!

Cockrell Butterfly Center Fall Plant Sale Oct. 8!

This time of year, gardening can make you feel as hot as Priscilla Queen of the Desert

With water restrictions and heat advisories, who wants to get into that mess? The drought and high temperatures have also caused butterflies to suffer, leaving their numbers well below normal for the season. In addition to the gardens we plant to supplement their diet, butterflies rely on native plants throughout their lifecycle. The lack of rain has caused the wildflowers either to have a very short blooming period, or not bloom at all. That means a decrease in nectar for butterflies. Native host plants as well are suffering in the dry heat, leaving caterpillars short of food as well. Triple digit temperatures cause female butterflies to not lay eggs and in general cause the overall populations to languish.

But, there is good news.

Soon the triple digits should be a thing of the past and we can all get outside and start tending our gardens again instead of watching through the window as they shrivel. The butterflies will be back as well and we need to be ready for them.

HMNS Fall Plant Sale
Cockrell Butterfly Center Fall Plant Sale Saturday, October 8

If your garden needs perking up, head over to the Cockrell Butterfly Center’s Fall Plant Sale on Saturday, October 8th, from 9 to 11am, on the 7th level of the parking garage at the Houston Museum of Natural Science. We will have a wide variety of host and nectar plants to attract butterflies, bees and hummingbirds to your garden.

HMNS Fall Plant Sale
The Cockrell Butterfly Center is the perfect place to see gorgeous,exotic butterflies – but you can help
preserve these fragile wonders by creating a butterfly habitat for local species
in your own backyard.

Check out the list of available plants for more information.

Here are some tips for attending the plant sale:

1. Get there early. This year our sale is only from 9 to 11 am.
2. Bring a wagon to cart around your goodies.
3. We take cash, check and credit cards.

Spring Plant Sale!! This Saturday, 4/9

The Cockrell Butterfly Center is having its Spring Plant Sale Saturday, April 9, 2011, from 9 a.m. to 1 p.m. on the 7th level of the parking garage at the Houston Museum of Natural Science.

Make sure to get there early as plants do sell out! This post is by Soni, one of our Butterfly Center horticulturalists.

HMNS Fall Plant Sale
See more photos from the Spring Plant Sale on Flickr.

We have nectar plants and host plants to attract butterflies to your garden. This year, we have been working on propagating more native plants. This includes:

Black-eyed Susan (Rudbeckia hirta)
Giant Coneflower (Rudbeckia maxima)
Mexican Blanket (Gaillardia pulchella)
American Basket Flower (Centaurea Americana
Creeping Spot Flower (Acmella oppositifolia)
Maypop Passion Vine (Passiflora incarnata)
And others!

Tithonia
See more photos from the Spring Plant Sale on Flickr.

Some of you are probably seasoned butterfly gardeners, but some may be asking yourselves:

How do you garden for butterflies?

The answer is really simple. There are two types of plants that you need to have for a successful butterfly garden: nectar and host plants. Nectar plants have blooms that produce a sugary liquid that butterflies need to consume in order to survive. Some examples of these plants are Porter Weed, Echinacea (Purple Cone Flower), Zinnias, Rudbeckia (Brown and Black-eyed Susans), Monarda (Bee Balm), Lantana, Salvias, Eupatorium (Mistflower), Cuphea, Buddleia, and Tithonia (Mexican Sunflower) among many others.

Gaillardia
See more photos from the Spring Plant Sale on Flickr.

The other type of plants that you need are host plants. Some examples of these are: Asclepias (Milkweed), Passionvine, Citrus, Rue, Fennel, Aristolochia (Pipevine), and Cassias. These are plants that the female butterflies lay eggs on. Certain species of butterflies will only lay their eggs on specific plants such as the Monarch, which only lays eggs on Milkweed. If you see caterpillars on these plants, that is a good thing! Those caterpillars are baby butterflies! The host plant is their food source, which means that the caterpillar eats the leaves. If you want a garden to attract butterflies, but don’t want insects eating away at the foliage, just use nectar plants.

Create a Local Butterfly Habitat!

A lot of these plants are native to Texas and the good thing about this sale is that the Cockrell Butterfly Center specifically chooses plants that will attract the native butterflies and will perform well in the Houston area. If you are not sure what to do or have any questions about gardening for butterflies, our experts will be at the sale to answer them. Come early, the plants go fast!