Thursday, June 30, 2016

"Yuck-a" weevil takes a toll in my garden!

This is a bummer post, just so you know.   A few weeks ago while investigating why a formerly healthy row of Yucca 'Color Guard' plants were suddenly dying from the ground up I discovered holes in the base of the plants.

Agaves and yuccas have been the backbone of my landscape since I began working on this garden in 2009.  After all, they add so much and require almost no attention from the gardener.  Just plant and walk away.   About the only problem I knew of is what I had read in blog posts like "Evil weevils" from Digging on the demise of agaves and related plants from agave snout weevil attacks.  So when I discovered the damage, I knew just what it was.  Snout weevils had bored into the core to lay eggs and their larvae ate the fleshy insides on their way out leaving cavities in the base of the plant from which it cannot recover.  I removed the infected plants and surrounding soil, placed them all in tightly closed trash bags and deposited it all in the trash.

Before, we had three cheerful matching Yucca 'Color Guard' looking great along the driveway

After, not so great.

Surveying the rest of the garden I found several soft-leaf yuccas (Yucca recurvifolia) looked yellow around the base and literally broke off in my hands as I checked them.  This meant I had to take fast action.  Following the advice I found in Pam's post and verified through other sites we began to treat all agaves and yuccas with a systemic insecticide from Bayer with the trade name "Merit."  I rarely reach for the bug killer, but these plants represent a huge investment in time and money.  You can read more about the product at Tropical Texana.  Early spring is apparently prime time for infestation and the best time to use a systemic is in advance so I'm not sure how effective a late spring/early summer treatment will be.

It wasn't long before I noticed the sudden decline of one Beschorneria in a pot by the garage and found larvae holes in the base.  Oh no, not the Beschoneria!  Oh yes, it's toast.

At this point I found the larvae and a few weevils or beetles in the soil.  Warning:  Ugly scenes ahead!

Telltale holes in the base.  How supposedly flightless insects found their way up into a 20" tall pot is a mystery.

Rotten core

While I didn't capture any weevils, I found larvae.

For some reason the other Beschorneria is fine.  Since these were matching planters on each side of the door and I won't purchase another Beschorneria I'll move the remaining plant elsewhere.  Then I'll need to find something else for these pots.  I trimmed those yellow leaves after this photo.

And onward we go into the back garden where I have had to remove all my Manfreda 'Macho Mocha' and surrounding soil.  Is it the work of the actual Yucca or Agave Weevil?  Must be, I was too busy stomping and squishing to take an ID photo of the culprit but we noted two different types of beetles in the soil around the affected plants.  Manfreda 'Macho Mocha'  is described on websites I read as being particularly susceptible.

Larvae still wriggling in the core

This is not a Yucca weevil which is less shiny has a pronounced snout but it was in the soil as we pulled out plants.  Perhaps an opportunist taking advantage of holes drilled by another beetle.  I couldn't get a good look at the other darker beetle or see the snout.

Another Yucca recurvifolia in the crevice garden is toast.  One positive note is native Manfreda maculosa and Yucca rupicola or Twist-leaf yucca plant seem to be unaffected so far.  Fortunately a coveted Manfreda 'Chocolate Chips' Pam shared with me from her garden this spring had been potted up and placed inside the sunny screened porch and is just fine.  Not that pots are a barrier since the Beschoneria was in a pot but I think the combination of being on the enclosed porch and in a pot seems to have helped save it so far.

We're not done yet.  While checking the crevice garden for more yucca damage I noticed  Agave 'Blue Glow' had telltale signs of yellowing bottom leaves.

Even though most websites ID the Agave weevil as different from the Yucca weevil, there seems to be no difference in the damage.  Either I have both types or they are indiscriminate.


More plants and soil into the trash.

So now my agaves are under attack and I just brought home a new Agave Cornelius which will need to be protected.  Agaves are slow-growing so the chances they will take in enough systemic during summer's heat to ward off attacks from borers are slim but I will continue to treat and check.  And hope I have eradicated the little (bleeps).  At least I read they slow down in the summer.

Agave 'Blue Glow' with Bluebonnets in happier days.  We will miss this plant which was a favorite in the crevice garden.

How did these bugs get here?  Did I bring this culprit home from the nursery?  I have no idea.  All affected plants have been in the landscape for at least three years.  Since my only recent agave or yucca purchases are unaffected, I'm fairly certain it didn't hitch a ride to my garden from a nursery.   However it got here, there will be no more soft-leaf yuccas, manfredas, or agave relatives added to the garden for a while.

Resolving this issue may take years considering the massive numbers of beetles across our entire property.  Given the size of this infestation and the rapid takeover it's unlikely I could have stopped it unless I had been proactively feeding insecticide to my plants for the last year or two.  Drenching soil with systemic insecticide "just in case" is simply not the way I garden.

It's not easy watching so much of our planning, work, and enjoyment of the garden unceremoniously pitched in the trash bin.  Even as I continue to dig out plants and soil, I'm already moving past this and thinking what to do.   Summer heat is upon us now so I'll take some time and decide what to replace all those missing plants with.  I was so happy with the way things looked that it's hard to imagine not having these softer forms of spiky plants in prominent spots.  Some plants are less susceptible than others and I'll compile a list which will more than likely include a few of these Agave schidigera 'Shira ito no ohi' which seems less susceptible to the weevil.

Besides that, this plant just makes me smile.

Monday, June 20, 2016

Garden visits: Cliff's Garden

While browsing through NextDoor, a neighborhood website, I spotted a familiar name sharing photos of his beautiful garden.  Cliff volunteers at Warrior and Family Support Center gardens and Gardening Volunteers of South Texas (GVST), so I see him both places.  Of course, I asked to visit and was off to see his garden about 10 minutes away.  As usual, find the street and look for the best garden from the curb.   I knew this was the right place with their very own street sign.

Friday, June 10, 2016

New Plants!

What's even more fun than new plants?  Getting those plants for free!  These last of my spring plant acquisitions have found their place in the garden and, even better, they were all free of charge.

My haul across the top:  Bauhinia mexicana with unique pink bloom, chocolate plant (Pseudaranthemum alatum),  two native Salvia farinacea, Asclepia tuberosa milkweed, a very cute begonia with dotty leaves, and nicely variegated tradescantia.
Bottom row:  Native snapdragon vine (Maurandella antirrhiniflora),  a new larger blooming variety of pink turk's cap (Malvavicus arboreus),  cuban oregano,  native pink rock rose.

All for free?  Yes, most of the plants came from the City-Wide Plant Exchange at Festival of Flowers where just over 1,750 plants were exchanged during this year's event sponsored by Gardening Volunteers of South Texas (GVST) annually.

I simply took in a cart load of extra plants, turned them in for tickets, then exchanged my tickets for new plants brought to the exchange by someone else.  Just a little work on my part to dig and pot up extras from my own garden and I get to bring home new and different plants.  Each year I find a few special native plants on the tables and those are the ones I scoop up first.  This year I snagged a new variety of pink turk's cap, similar to Pam's Pink, except it has a larger bloom.  I'm giving away a secret here, but sometimes plants from the GVST plant sale booth end up mixed in with exchange plants.  GVST propagates plants for sale at gardening events throughout the year.  Their plant sales booth is just visible in the back right of the photo above.  The GVST propagation team works with Texas Agrilife extension service to introduce new varieties so most are plants you won't find at retail nurseries for a while.  That new variety of pink turk's cap was set out on the tables to help "seed" the exchange for early arrivals.  Best to arrive early anyway before the "cart park" fills up.  My cart is out there on the back left of the photo.  If you plan to participate next year, please read (and follow) the rules on the link.

While there is a $6 admission charge to Festival of Flowers, you will get back so much more than that in access to vendor specials and informative seminars.  My new native milkweed plant was free at the door as a giveaway from our San Antonio Water System (SAWS) so if you stop by their table you've already cut your admission in half.

I volunteer a few hours of my time answering questions at the show so my admission is free.  That's me on the left with Laura Rogers and between us we answered some tough questions from local gardeners.  The stumpers were descriptions of plants without photos.  Our advice is snap a photo and bring it with you--so much easier to ID a plant that way.

Photo courtesy of Anne Schiller, GVST
I was so excited to win a rare pink blooming Bauhinia mexicana or Mexican Orchid as a door prize at the Gardening Volunteers of South Texas meeting in April.  I can't wait to see those delicate pink blooms.  I know the bloom in the photo below looks white, that's because it's a young plant that's been in the shade.

Next up is Agave cornelius.  Just look at those ruffled edges and great color.  As a bonus, it's cold hardy and forms a neat rosette instead of throwing out pups on long runners like most Agave americana varieties.

That was free too?  Sure was, I used a gift certificate sent as a "thank you" from GVST for volunteering at the Watersaver Landscape Tour back in early April.

Did you notice a common thread with all my new plants?  It's Gardening Volunteers of South Texas (GVST).  If you've been thinking about getting more involved in San Antonio gardening, joining GVST is a great way to get started.  Gardening Volunteers of South Texas holds classes at The San Antonio Garden Center from noon to 3pm on the third Monday of each month.  For a five dollar donation you get lunch, a lot of great information on gardening in San Antonio from two knowledgeable speakers, and a chance to win great door prizes.  So come on out, I'll see you there.

Wednesday, June 1, 2016

Wildlife Wednesday June 2016

Wildlife in the garden during May brought a couple of special butterfly sightings and a few other amusing wildlife antics.  Wildlife Wednesday hosted by Tina at "My Gardener Says..." presents bloggers an opportunity to share wildlife in the garden on the first Wednesday of each month.

Butterfly identification can be challenging as with this striking white butterfly.  At first I thought it was a Cabbage White Butterfly, but it lacked the dark edge on the forewing and has distinctive bands instead of spots.  After searching I'm going with male Checkered White Butterfly (Pontia protodice) which is so much better since Cabbage White Butterflies are not native.  Interestingly, they both use members of the cabbage and mustard family as host plants.  I could not find any information to confirm whether these butterflies consume the invasive weed Rapistrum rugosum or Bastard Cabbage which has been decimating our native wildflower fields.