Monthly Archives: May 2019

Flowering trees, trees

Tree Varieties You’ll Love

We have Joyce Kilmer to thank for her poem ?Trees? that starts with the famous line:
I think that I shall never see
A poem lovely as a tree.

In nature and in the garden it?s the trees that get most of the attention. Cambridge Dictionary defines the Wow Factor as a quality or feature?that makes people feel great excitement or admiration. Majestic and dramatic, no matter the size, a tree makes a garden or landscape speak that it?s here to stay.

Brahea armata – Mexican Blue Palm

Recently I had the pleasure to spend some time in a historic garden that dates back to the 1800?s. Last year this garden was featured on the Garden Conservancy Santa Cruz Open Days. The Conservancy?s mission is saving and sharing outstanding American gardens so I was thrilled to tour this garden, be introduced to several new tree varieties plus see some old favorites that might just work in your garden also.

Many of the hundreds of tall bearded iris were still blooming in the garden as well as early flowering perennials and shrubs. I didn?t see any dragonflies flitting about on this particular day but the stunning ornamental gate and mosaic created on one of the garden paths both feature dragonflies and I?m pretty sure they are regular visitors. The garden is called Odonata which is the order of carnivorous insects encompassing dragonflies and damselflies.

An unusual flowering dogwood from Mexico. Cornus florida ‘Pringle’

One of the most unusual flowering trees in Odonata was the Mexican flowering dogwood. This small ornamental tree, a cornus florida subspecies called ?Pringle? had the most unusual flowers. Their white bracts don?t fully open giving them a Chinese lantern look. This tree holds its foliage later than the more familiar Eastern dogwood and has reddish fall color. Glossy red fruit that forms later in the season is readily eaten by birds. This tree is showy and best used where the flowers can be appreciated.

Wedding Cake Tree or Cornus controversa ‘Variegata’

Another dogwood variety growing nearby was also new to me. Cornus controversa ?Veriegata? (Wedding Cake Tree) is graceful and spectacular with beautifully layered horizontal branches. Winner of the prestigious Award of Garden Merit by the Royal Horticultural Society the tree was covered with showy creamy white flowers in flattened clusters. Later the blossoms will give way to black berries in late summer that is, if the birds don?t get them first. Fall color is a lovely yellow color.

Golden Chain Tree aka Laburnum x watereri ‘Vossii’

Also in bloom, a laburnum x watereri ?Vossii? (Golden Chain Tree) looked spectacular with long, drooping clusters of lightly fragrant, bright yellow flowers. This handsome tree has a beautiful spreading canopy of bluish-green foliage and is a great choice as a single specimen or even in a group planting.

Honorable mention awards would have to be shared between the red form of Henry Lauder Walking Stick ?Red Dragon? and the white Flat Rock leptospermum. Well maybe the cryptomeria japonica ?Dacrydioides? (Whip Cord Japanese Cedar) or the pinus wallichiana ?Zebrina? (Striped Himalayan Pine) would also place.

Pittosporum ‘Silver Magic’

There were so many other note-worthy specimens in this garden. From showy shrubs like pittosporum ?Silver Magic? to large palm specimens such as Mexican Blue Palm and a giant bromeliad variety called a puya this garden is a landscape designer?s candy store. I even enjoyed the more common plants like lomandra ?Platinum Beauty?, variegated fortnight lily, a huge heuchera ?a la Rochette? blooming alongside a brilliant blue native pentstemon as well as gold flowering Moonshine yarrow.

It was an afternoon to remember between rain storms.

pruning wisteria, vines, winter pruning, wisteria

Wisteria – Growing Tips & Maintenance

A pink Chinese wisteria covering a pergola in Bonny Doon

Wisteria season is winding down unless you have a repeat bloomer like a ? Cooke?s Purple? or ?Amethyst Falls?. I?ve heard it all: ?Why doesn?t my wisteria bloom?? or ?I planted a wisteria in the wrong place, how do I get rid of it?? or ?I love my wisteria but it?s taking over the porch ?? (insert garage, house, shed or other structure) Seems we either love ?em or hate ?em on our own property. Growing somewhere else they are always the stars of the spring garden. If any of this sounds familiar to you here are some tips on how to handle yours.

Wisteria are one of nature?s most resilient survivors. They are able to withstand and recover quickly from difficult conditions. To some they are a little too tough for their own good with a growth rate rivaling bamboo during the summer. If you dream of a wisteria-covered pergola shading your patio here are some maintenance tips that are sure to keep both gardener and vine happy.

A pink wisteria growing under a fragrant purple variety covers a gazebo.

Wisteria are so vigorous they can be pruned at any time, keeping them in bounds and clearing out unwanted or dead growth. Prune out any stems you see extending into eaves, windows or shingles. If yours has gotten away from you, you can even prune it down to the ground and start over with training although you?ll have to wait a few years for your vine to bloom again.

To their control size major pruning is done during the dormant season. Start by trimming the long tendrils that grew over the summer back to about 6 inches from the main trunk. Cutting the tendrils back in this way will initiate flower bud development, neaten the plant up, and show off the attractive trusty, gnarly character of the vines.

Whatever time you do renovation pruning remember the response of the wisteria to aggressive pruning is to literally explode with new runners. They put energy into new vegetative growth at the expense of flowering. Make sure you keep up on ongoing maintenance pruning by removing all unwanted runners right to their point of origin. Then prune back the others to 3 buds or sets of leaves. Repeated pruning of these runners is what will eventually give you spurs of wood, short laterals that in turn will provide you with flower clusters. You need to prune these runners all season long which ends up being every 3-4 weeks.

Do not fertilize your wisteria. They do not flower well if there is an over abundance of luxuriant growth. Over feeding also ends up giving them the means to become unmanageable monster. If you have trouble getting your vine to flower an application of a high phosphorus fertilizer may promote blooming.

A diligently pruned wisteria at Filoli Garden

Maintaining a wisteria requires some diligence but the reward is worth the effort. Remember this especially during winter pruning season to make summer maintenance easier. If you find that the wisteria vine has invaded a nearby bed, cut roots with a shovel below the soil line to control any that have wandered.

Which variety of wisteria should you get to cover your arbor, pergola, tree or other structure?

A Cooke’s Purple wisteria growing on a pergola in Boulder Creek.

Chinese varieties such at ?Cooke?s Special? have clusters of fragrant blue-purple flowers 20 inches long. This variety can re-bloom which makes it a favorite. Chinese wisteria can take up to 20 years to mature enough to produce flowers, but once it has matured, the plant is very long lived and can live up to 100 years.

Japanese wisteria like ?Caroline? bloom early with mauve flowers. ?Royal Purple?. known also as ?Black Dragon? , has sweetly scented dark purple flowers. Japanese wisteria are most effective when grown on pergolas so their long flower cluster can hang freely.

American wisteria, native to more eastern areas of the U.S. is a smaller, less invasive species that grows ar about a third the rate of Asian wisteria. ?Amethyst Falls? blooms at an early age with lightly fragrant purple racemes. Use in containers for porch or patio, train up an arbor or trellis or as a small free-standing tree.

Silky varieties produce a profusion of short, 6 inch, fat clusters of strongly scented flowers that open all at once. They have velvety seed pods and bloom best in full sun.

All parts of the wisteria vine contain a toxin known as wisterin which can cause stomach upset. Growers should also be wary of pets and children eating the flowers or seed pods.

citrus trees, fungal diseases, plant problems

Plant Problems- What’s a Gardener to do?

Just one of many banana slugs in my garden

Everything was growing nicely in the garden until the banana slugs and squirrels started eating me out of house and home, fungal leaf spots and aphids appeared and the gophers and deer decided they really liked my plants. What?s a gardener to do?

Troubleshooting is a form of problem solving. And whether it?s your car, your smart phone, an irrigation system or yellowing leaves on a plant the goal is to find the solution and make everything work again. When you eliminate the potential causes of the problem hopefully the solution restores everything to its working order. Sometimes this is easier said than done as we all know.

A few weeks ago I received a text with pictures of some plants with leaf spots and was asked for a solution. Over the winter we received a lot of rain so I wasn?t surprised. But if this were mid-summer I?d suspect that the plant leaves were burned by the sun and not getting deep enough irrigation. At this time of year, however, black or brown spots on leaves are fungal or bacterial problems and should be treated with an organic fungicide like Serenade which is non-toxic to bees and beneficial insects, Neem, copper or sulfur spray to prevent and control spreading. Affected leaves should be discarded.

The subject of how much fertilizer and what kind came up in another troubleshooting email. The issue was whether to use an organic high phosphate fertilizer in order to encourage bud development on a notoriously short-season tree dahlia. A single spring application of rock phosphate should be sufficient. Sometimes adding too much phosphorus can actually hurt a plant, preventing the uptake of other nutrients necessary to prevent other deficiencies. A balanced fertilizer containing all three nutrients- nitrogen, phosphorus and potassium-was recommended for the remainder of the season.

Winter yellow leaves on Meyer Improved lemon

Then there are the problems in my own garden. Well, it seems I am always trying to solve something with plants, pests or critters but now it?s the lemon tree. The older leaves of this tree are yellow. The new growth looks fine so it isn?t an iron deficiency where young leaves display green veins along with a yellowish color.

It isn?t a nitrogen deficiency either where the mature leaves slowly bleach to a mottled irregular green and yellow pattern, become entirely yellow and then are shed while the discoloration spreads to the younger leaves. I fertilized in March with an all-purpose balanced fertilizer. Citrus are heavy feeders and require a steady source of nitrogen, the ideal citrus fertilizer having a ration of 3:1:1 (N:P:K)

After eliminating other mineral deficiencies or overwatering as the problem I decided that my lemon was simply dropping interior leaves which is normal after winter but I wanted to trouble shoot all potential causes to be sure citrus greening wasn?t the culprit. If it had been this deadly disease the leaves would have exhibited an asymmetrical pattern.

To quote Sherlock Holmes ?Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.? I?ll try to remember that when I?m troubleshooting my next problem in the garden. Oh and by the way my banana slug relocation program is going well.