Yarrow (Achillea millefolium): A Seasonal Look

The joy of summer green and beauty of cool white are accurate descriptors of the Yarrow, Achillea millefolium, in my garden.   Gifted to me as a passalong plant some 20 odd years ago, it is a plant that is lovely to view and easy to grow.

A member of the Asteraceae (Aster) family, common Yarrow grows throughout a large area of continental North America.  According to the Lady Bird Johnson Wildflower Center (LBJWC) plant data base, the plant is classified as both a single species with varieties and as multiple distinct species. 

My guess is that mine is the true native variety, considering how long I’ve had the plant (hybrids and cultivars are now more readily available than when I was given my Yarrow starts) and that the blooms are a natural snowy white, rather than hybrid pink or yellow.  Yarrow’s fine foliage is 5-6  inches tall and acts as a lacy ground cover for most of the year.   In early spring, the graceful low-growing foliage grows anew and also sends bloom stalks upward to meet the spring sky.  In time, buds appear at the terminal ends of multiple branches.

Depending upon sun amounts received, Yarrow bloom stalks can reach upwards to three feet.  Mine all grow with some shade, which is ideal for Yarrow. While Yarrow is a great plant for shade or part shade, in my experience, deep shade will render the plant a full-time, evergreen ground cover, but it abandons all attempts at blooming.

But with some sun, the garden benefits from both beautiful foliage and flowers.

By May and throughout June, the disk flowers open for pollinator business and gardener admiration.

Most of the pollinators I see on Yarrow are of a diminutive sort; these include many types of flies, tiny native bees, and the smaller butterflies.

This Horsefly-like Carpenter bee is one of the larger pollinators to visit my Yarrow blooms.

 

I grow Yarrow in several areas of my garden and it’s complementary to other members of a perennial garden.

Additionally, Yarrow adds a prairie quality to the summer garden.   The prime bloom time lasts about 6-8 weeks, but even when the flowers fade, Yarrow remains handsome.

 

Into July, a toasty quality appears on Yarrow as the pure white flowers go to seed. As summer settles in with its heat and glaring sun, the flowers decline, seeds develops and Yarrow’s pure white tops turn tan and toasty.

The white Yarrow blooms are hard to improve upon, but as the plant undergoes its seasonal evolution, I don’t mind the transition from blooms to seed.  It’s a gradual transition and the plant remains attractive for most of summer.

I’ve seen House Finches and Lesser Goldfinches nibbling at the Yarrow seeds, so along with it acting as a good pollinator plant, other wildlife benefit from this perennial as its growing season advances.

Yarrow’s flower-to-seed heads beauty doesn’t last forever, though. Typically, by the time the flowers are long done and the seed heads are crumbling, the bloom stalks are also bent with age and environmental impacts.  After all, they’ve held aloft sweet blooms and nutty seeds for many to enjoy through spring thunder and wind storms and searing summer sun.   Bottom line:  Yarrow is messy by late summer.

Sometimes, parts of the foliage turns brown in sympathy with the beige seed heads.

Once the bloom stalks have flopped for good, I cut them back.   There’s no real art or skill with this pruning, it’s just about cutting the now-brown stalks at or near the ground, which usually reveals new ground cover growth settling in place for the coming seasons:  autumn, winter, spring.

In the above photo, the remains of pruned stalks lie disguarded outside of the garden’s limestone border; you can see new Yarrow foliage emerged on the other side of the limestone.  This foliage will be the basis of the ground cover which will flush out during autumn and remain evergreen in winter.

In especially dry summers and/or if I haven’t irrigated, the new ground cover foliage endures a breaking-in period where it’s sparse and ratty looking; Yarrow down-time usually occurs in August.  Fortunately, the ugly duckling phase doesn’t last long,  because the foliage quickly greens up and fills in with help from the shorter days and regular rainfall that September normally brings.

 

While Yarrow flowers produce seeds (those finches are eating something!), the only spread I’ve observed is with the roots of established plants.  In this shot, the foliage has crept out of the border of the garden and into a walkway.  I’m tolerant of this creeping action–to a point.  When I’ve had enough of Yarrow’s teen-like testing of boundaries, I simply dig out the offenders and toss them into the compost bin or give to another gardener.  With healthy attached roots and a smidge of extra watering, Yarrow transplants easily.

 

By autumn, brilliant green, ferny foliage returns and the groundcover is set for the upcoming cool seasons.

I’ve experienced no insect or disease problems with Yarrow and it’s a drought tolerant plant.   Another plus with planting Yarrow is that it is deer resistant.  Its foliage and flowers are fragrant and has been used for medicinal purposes.  I’m not big on cut flowers, but Yarrow is a nice addition to a vase.

Because it’s somewhat statuesque from April to August and low-to-the ground for the rest of the year, care should be exercised when considering placement of Yarrow:  it works in the back of a bed during its peak blooming time, but will be unseen for the remainder of the year. My solution has been to plant all my Yarrow along pathways and pair it with similar sized plants.

Whether you purchase Yarrow or it’s given to you as a passalong plant, treasure it!  Yarrow is easy to grow and lovely to look at.

In Spring:

 

Summer:

My sweet old dog, Asher, enjoying the garden one afternoon, several years ago.  Asher died late last summer.

 

Late Summer:

Yarrow in its ground cover mode planted with Chili pequin (top right) and a container plant (left).

 

Autumn and Winter:

 

 

Moss Rocks: Wildlife Wednesday, June 2019


We recently realized that our pond was leaking–not too much, just enough.  The pond leak isn’t a first, it’s happened before.  The most likely place for a pond to spring a leak is at, near, or around the waterfall, so unplugging the pump and dismantling the rocks which make up the waterfall are steps one and two for diagnosing a disappearing water act.

A slight slippage of pond liner, coupled with inappropriate rock placement, allowed for some (well, more than some) water diversion into the bordering soil and away from the pond.  We repaired the liner, re-stacked the rocks, and the pond is back in action and holding a constant level of water.  The fish are happy and swimming, the pond flowers are lovely and blooming, and the pond is no longer wasting water.

After we turned off the pump and removed the rock around the waterfall to watch for  water level change, I observed this Blue Jay, Cyanocitta cristata, hopping around the disassembled rocks, pulling up bits of moss from those that had been in water.

That the jay was interested in the moss is a curiosity.  Blue Jays are omnivores and eat a variety of things:  seeds, nuts, grains, insects are all on their favorite foods list, but they sometimes steal nestling birds and dine on small animals (mammals and invertebrates).  As well, they’re known to occasionally scavenge dead birds and animals.  I don’t know that Blue Jays like salads, but this jay wasn’t eating the moss, nor can I find information that Blue Jays partake of this particular green in their diets.

Blue Jays do use grass for nesting, though;  might they also use moss?  Males are typically the gatherers of nesting material, while females are the builders of the nests.  Could the jay be in the process of gathering nesting material?  Yes, that’s certainly a possibility, though it seems a bit late in the season for family planning and house building.  Blue Jays only produce one brood per year and when I’ve observed Blue Jays and their nests, the babies fledge in May, or early June at the latest.  That said, Jays will abandon nests if a predator attacks or if some other calamity befalls the eggs or nestlings.  This spring has seen some spectacular thunderstorms with high winds and driving rains, perfect for dislodging nests–and nestlings–from trees.  Additionally, owls and hawks live and hunt in our neighborhood, so it’s reasonable to think that this bird’s first brood didn’t fledge successfully and he and his partner are in the family way again.

Mr. Jay was choosy about his moss.   He plucked moss from a rock, then dropped some of it. He bounded around to other moss rocks, snagging more in his beak, dropping that, then gathering other bits.  He acted as if he was looking for just the right sort of moss.

After a time and done with the moss-work, he flew away.

My best guess is that he was helping his mate build a nest–maybe their first, probably their second. There are no occupied Blue Jay homes in my trees, so I’ll never know for certain if the plucked moss is destined to feather a nest.  Maybe in a month or two I’ll see a fledgling Blue Jay, nearly as big as her parents, ruffling her feathers, squawking impatiently, and begging for food.

How is your wildlife?  Are they foraging in your foliage or feasting at your feeders?  Are the wild things in your garden chasing competitors, wooing mates, or raising families?  Please share your wildlife garden stories and remember to leave a link when you comment here–happy wildlife gardening!

Return of the Blues: Wildlife Wednesday, March 2019

Ah, the winter blues.  More accurately, the late winter blues.  Blue Orchard Mason bees, Osmia lignaria, are exiting their year-long incubation chambers and buzzing my garden.

The goal for their short lives is to mate, rummage around flowers and foliage for nesting material, lay eggs, and pack the eggs safely to ensure the next generation of bees who will appear, on cue, next February.

The blue bee bonanza is an annual event in my garden.  These beautiful insects–an eye-popping, rich, iridescent blue–zoom from the native bee houses where they grow up, to the garden and beyond, and then back again, as they mate and then gather pollen and other material for the next generation’s nesting chambers.

These bees are important for commercial orchards, but thrive in welcoming home gardens, too.  In our garden, we’ve placed several boxes with drilled wood and lengths of cut bamboo.  These bee houses are utilized by a variety of native bees throughout the year.  Because the Blue Orchard bee adults emerge in February, they’re the first native bees to pack away their babies in the bee houses.

Packed nursery holes, as well as some where a bee (or bees) have exited, and a new adult.

After mating,

…the females begin their egg-laying process in a hole in wood or masonry which is of a size and length that the adult female finds appealing.  The first eggs laid–those at the back-end of the cylinder–are female, and the eggs at the front–potentially the most exposed–are male. Between each egg laid, mom bee builds a wall of mud and pollen so that each is snuggled into its own room.  The entire nursery, all chambers therein, is then sealed firmly until the next year.

Do the girls get pink rooms and the boys, blue?  Nah, the rooms are gender-neutral, as far as color choice goes.  However, gender differentiation is present: the female eggs-larvae-adults are at the furthest end of the nursery cylinder so that those most responsible for successful procreation are best protected, or so suggest the entomologists who study these bees.  The male eggs-larvae-adults are situated at the front of the nursery cylinders, emerging as adults first, so that they’re ready, eager, and awaiting their potential mates.

The two bees in this photo are males; one is fully emerged, the other peeking out, ready to take on his corner of the world.

Males have a white patch on their faces which is a mustache-like clump of white hairs.

Hairy dudes.

This fella rested on an upturned plastic bin under one of the bee houses.  He posed handsomely for me.  Or was he challenging me to a duel?  Or perhaps wondering what I am?  Who knows what a bee thinks?

The females (with the males, of course) mate, then begin preparations for laying eggs and provisioning for their offspring.  This female wriggled and writhed around the pollen-laden center of a Desert mallow bloom. 

Unlike honeybees, who carry their pollen packs on their legs in what are formally known as corbiculae or pollen baskets; I call them pollen pantaloons, but that’s just me. Blue Orchard bees,  members of the Mason bee family, carry gathered pollen on their tummies.  This is the best shot I  managed of a female heading into a nesting chamber with pollen.  These gals are fast fliers!  I’ve observed creamy white pollen-coated tummies, as well as cheery yellow and orange, color depending upon what bloom, or blooms, the female worked.

The females fly into the holes head-first, making their way to the back of the cylinder, then working their way forward–one egg and egg prep–at a time.  Mom bee rolls the pollen into balls, adding nectar and microorganisms, to make pollen bread. Each egg is laid on its own ball of pollen bread, which will be the food source for the larvae.  A mud wall is built, sealing in the egg and its food source.  Then mama works on the the next egg and chamber, so it goes until she reaches the front of the hole, which she seals thickly with mud and pollen.

The female has chosen this bamboo cylinder for her nursery. To the left, see the two cylinders with holes; adult bees, plopped in last year, have exited their nursery chambers.

I don’t grow any fruit trees, though I have some early spring blooming trees in my garden  There are flowering fruit trees in my neighborhood–peach, apple, and pear–and I expect that the blue bees nesting my garden visit those flowers.

Building native bee houses, or hotels, is easy.  Using untreated wood and providing a variety of different sized holes for different sized bees, you’ll attract a wide array of native bees to your garden.  You can even leave cut logs from downed, or pruned, trees in your garden, and with some aging of that wood, the native (carpenter) bees will find them.  Check out these links for instructions and ideas about attracting these fascinating and beautiful pollinators to your garden.

https://www.nwf.org/en/Garden-for-Wildlife/Young/Build-a-Bee-House

http://www.foxleas.com/make-a-bee-hotel.asp

As much as the appearance of new buds on trees or the thickening of bloom stalks on spring perennials, the arrival of the adult Blue Orchard bees heralds the onset of Spring in my garden.  New life emerging and continuation of the alliances between flowering plants and their pollinators confirms a time-honored environmental zeitgeist of the natural world.

What indicates spring–or autumn–for your garden?  Please share your wildlife garden observations and insights, then leave a link to your post when you comment here–and happy wildlife gardening for March!