Butterflies, Butterflies

Western Swallowtail enoying the nectar of a Butterfly Bush.

My Butterfly Bush (buddleja dividii) has started to bloom and it’s a Western Swallowtail butterfly magnet. Butterfly species each have their own life cycle and habits and it’s fascinating to watch them as they go about their lives.

I live on Boulder Creek where the steep banks are covered with blackberries. The Himalayan blackberry has choked out the native species here but the swallowtail butterflies visit the white flowers regularly to harvest nectar. Later in the summer they will relish the ripe berries.

Summer butterflies live only for a week or two. During that time the butterflies mainly search for food and a mate. They have a keen sense of sight, smell and taste. Having large eyes they can see many colors including those in the ultraviolet range that we can’t see. Many flowers have ultraviolet patterns that butterflies find especially attractive. Butterflies can detect movement better than we can. If you’ve tried to get a photo of one in your garden you know how hard it is to sneak up on them.

In addition to chemical receptors on their antennae, butterflies can taste food with their tongue and even their feet. They have thousands of dusty scales that cover their wings and body and absorb heat. They can make their wings tremble to speed up the warming process and even orient their wings to the sun to absorb heat more quickly.

Last year there was a huge hatch of Tortoiseshell butterflies looking for nectar of our native ceanothus. The California Tortoiseshell butterfly is a common butterfly that lays its eggs on ceanothus. After the CZU fire we have an abundance of this succession plant as the soil-stored seeds germinated after the fire broke their dormancy. These seedlings can account for more than half of the plants present in burn areas. If you’ve visited Big Basin State Park or any of the other burn areas, ceanothus are pretty darn happy with all the extra space and sun they are now getting.

Tortoiseshell butterflies have an interesting life cycle as do all butterflies. With three generations per year, they fly here from the Sierra foothills where they lay their eggs on ceanothus. Then those hatch and feed, morph into butterflies who fly to the foothills to repeat the process. Larval food plants include several species of Ceanothus. Adults feed on flower nectar, sap, fruit and mud. They live for 10 months or more.

The Tortoiseshell is no stranger to our mountain. After the Lockheed fire this same phenomena happened when the ceanothus were head-high. After hatching here they took flight to the mid-elevation Sierra Nevada to lay eggs on a different species of Ceanothus. After that generation denuded the patches of Ceanothus there those adults flew to the highest elevations to eat yet a different species of Ceanothus. Then the adults flew all the way back to Monterey Bay to lay eggs on our Ceanothus and start the cycle over again.

We have about 90 species of butterflies in the Monterey Bay Area. Many of these occur only in our mountains, forests and chaparral environments. They are easy to attract and make a permanent feature in your landscape. Here’s how.

A butterfly garden should include plants that accommodate all stages of the life cycle – egg, larvae, pupa and adult . When both adult nectar and larval host plants are available, they will attract and support a butterfly population. In addition to the right plants, your garden should also have sun, a water source, protection from wind and plants in clusters. When maintaining your garden avoid the use of insecticides, including BT.

As adults, most butterflies feed on the nectar of flowers. Some local butterflies, like the Mourning Cloak and Red Admiral, feed primarily on rotting fruit or tree sap for moisture and nutrients while the California Sister feeds on aphid honeydew.

In the larval stage, most butterfly species are limited to a single plant family and occasionally a single genus. To attract more Western Tiger Swallowtails, for instance, provide larval host plants such as willow, sycamore, alder, big leaf maple, sycamore, plum and ash. Common Buckeye lay their eggs on mimulus and verbena while California Sister use the coast and canyon live oak. Planting a variety of grasses and shrubs like ceanothus, buckwheat, coffeeberry, bush lupine,manzanita and perennials like redwood violet, California aster and wallflower will attract a variety of local butterflies. If your garden is near a wild area that naturally supports the caterpillar stage, you can plant just the nectar plants to attract butterflies to your garden.

Filling your garden with nectar producing flowers is the fun part. Adult butterflies rely on sugar-rich nectar for their daily fuel. Different species have different flower color and shape preferences. Many butterflies produce scents that attract the opposite sex and many of these scents smell like the flowers that they are attracted to and visit. The scent of these butterfly-pollinated flowers may have evolved as an adaptation to ensure their survival.

Butterflies typically favor flat, clustered flowers that provide a landing pad although larger butterflies can feed on penstemon and salvias while hovering. Unlike bees, butterflies can see red and are attracted to brightly colored flowers. Pink, red, orange, yellow and purple are the most attractive nectar source flower colors but they also use blue and white.

Consider the blooming time of each plant. Having plants blooming in the sun for many hours in the day will lengthen your viewing time. Nectar rich flowers include yarrow, aster, verbena, scabiosa, buckwheat, toyon, salvia, erysimum, zinnia, lantana and coneflower.

In addition to nectar, butterflies need a source of water and salts. A patch of mud kept wet year round or a shallow depression lined with pebbles and kept moist will work fine. Also provide some flat rocks for them to bask in the sun in an area protected from the wind by shrubs.

Having a garden filled with birds, bees, butterflies and other pollinators is fun and easy.

Where are the Dog Days of Summer?

What would summer be without sunflowers?

It’s been a cooler summer than the last few years. I’ve probably jinxed it now by mentioning that thereby insuring August will be a scorcher. But for now plants are happy they haven’t had to cope much with the “dreaded over-86-degree” weather when they can’t photosynthesize. It’s a good year also for those gorgeous dahlias and sunflowers, too. So will we have “The Dog Days of Summer” this year?

The Romans associated the weather from 20 days before to 20 days after the conjunction of the “Dog Star” with the hot days of summer. This falls between July 24th and August 24th. The name “Dog Star” comes from the ancient Egyptians who called Sirius, the Dog Star, after their god, Osiris. His head in pictograms resembles that of a dog. When the Dog Star rises in conjunction with the sun some felt the combination of the brightest luminary of the day, the sun, and and brightest star of the night – Sirius – was responsible for the extreme heat experienced during the middle of the summertime. Since Sirius is the brightest star in the night sky it’s reasonable to guess that it adds some heat to the earth but the amount is insignificant. We now know the heat of summer is a direct result of the earths tilt, but now you know… the rest of the story.

As summer rolls along you may become more aware of the different microclimates in your garden as some of your plants that used to get along just fine might be showing signs of stress. Taking note of these changes in the performance of your plants is what makes for a more successful landscape. When the weather cools towards the end of September you will want to move or eliminate those plants that aren’t thriving. Be sure to keep a thick layer of mulch on the soil around your plants to conserve that precious water you do allocate to each of your irrigation zones.

One thing I notice when I visit gardens for a consultation is the existing drip system has not been modified for many years, if ever, to allow for the growth of the plants. The emitters which were originally placed at the base of each plant are not even close to covering the current size of the root zone. The crown of the plant is getting overwatered with each cycle but the rest of the plant is bone dry. Time to add more emitters and move them away from the middle of the plant. No sense wasting water that’s not doing the plant much good.

The Dog Days of summer may be affecting our gardens but it doesn’t have to stop us from being out in the garden. The joy of gardening can take many forms including adding a wind chime, bird feeder or bird bath. Groom plants that need some cleanup. Many perennials benefit from a little haircut at this time of year to extend their blooming into the fall season. Santa Barbara daisies fall into this category. Lavenders will keep their compact shape by pruning a third of their branches now. This forces new growth in the center so the plant doesn’t get woody.

Deadhead flowering annuals and perennials as often as you can. Annuals like marigolds, petunias, zinnia and cosmos will stop blooming if you allow them to go to seed. The same is true of repeat blooming perennials like dahlia, scabiosa and lantana. These plants know they’re on this earth to reproduce. If they get a chance to set seed, the show’s over- they’ve raised their family. Try to remove fading flowers regularly and you’ll be amply rewarded.

Plant Facts

All trees, including redwoods, communicate with each other.

My friend, Evan, often shares with me interesting studies about plants. Did you know that older trees share intelligence with young trees? Scientists have recorded how birch trees use electrical signals to communicate. How do they do this?

All living organisms have an electrical system. This study showed that the older trees, who had prior knowledge of an event like a solar eclipse, shared this knowledge hours ahead of time with younger trees. Because a tree relies on normal day-night cycles to transport nutrients and regulate water and reproduction, upsetting their internal clock, even briefly, can divert energy from defense chemical production which keeps pathogens and predators at bay. Sharing this information by the elders in the forest protects the young who may not have experienced such an event before.

What other fascinating things do plants do? I was very intrigued reading an article in Audubon magazine by Nathan Ehrlich. Scientists have discovered that plants give off electrical impulses in response to threats. Polygraph expert and former CIA interrogation specialist Cleve Backster confirmed this when, on an impulse, he hooked up a tropical dracaena to a polygraph and threatened the plant with a flame. The dracaena displayed the same electrical signals that people do when they lie. From lettuce to bananas, the results were similar.

Biologists Baldwin and Schultz published work suggesting that some plants can communicate through the air. When the researchers threatened poplars and maples they found that nearby trees, with no physical contact, released defensive chemicals that inhibit digestion, thus hindering predators’ ability to consume the trees leaves or bark.

Plants have many ways to defend themselves. One common way is by being poisonous or irritating. You can get severe eye burn if you get the toxic sap from a euphorbia in them. You just have to accidentally rub some sap near your eyes to trigger a reaction that will require a trip to Urgent Care. The pain can last for days and has been described as a very painful experience. Euphorbias are very deer resistant and drought tolerant and are being used more and more in gardens. Great plant that requires respect.

Many of us are growing milkweed (Asclepias) to attract monarch butterflies. The milky sap from this plant protects the monarch from being eaten and can cause the same painful burning of the eye. I read of a case where a gardener’s clothes brushed some stems while she was tending the garden. Later she wiped the sweat out of her eyes and didn’t realize she had also touched her pants. She ended up with cornea burn causing temporary blindness and had to take strong pain relievers and steroids to elevate the pain. Yikes.

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