Archive for Spring Gardening – Page 2

Summer Watering Tips

Lawn_Watering_RotationFirst Rule…Do No Harm.  If you are watering every day, this is harmful and as far as you can get from the ideal watering practice for your plants’ health and for growing in your design.  Plus you will be accidentally training your plants to be shallow rooted and water hogs.  One is not good for the plants and the other not good for your wallet.  If this is how you have been watering for years and you want to change, let’s talk.

Newer Plant Material:  I consider any plants that have not been through a summer to Carol_Roger_newsletterbe a first year plant.  Plants 2 or 3 years old are established plants.  I typically have clients start watering first year plants every 2 weeks in April (depending on weather conditions in the Pacific Northwest).  This can continue into mid-May most years but by the end of May new plantings should be getting watered once or twice a week.  When we start having 80 to 90 degree weather, first year plants should be watered 2 to 3 times a week maximum, not every day.  We want to manage the plants water needs with other methods besides over watering.

Don’t wait until you see signs of stress – it can be hard to get moisture back into clay soils once they dry out.  Do you see leaves wilting, scorching, crumpling, or dropping?  Here are some ways to save a stressed plant:

Dead plant water blog

Clogged irrigation emitter equals plant loss – check emitters.

(1)  In the evening, after the sun goes down, hose down the leaves, to cool them off.  Or hose them down very early in the morning (before 8 a.m.).  Never sprinkle leaves after 9 a.m. in sunny weather, this will create scorched (toasted) leaves and flowers.

(2)  Cover your plants’ leaves for 3 days or less.  Covering plants helps them conserve water loss.  When not exposed to the sun, the cells  in the leaves will close.  And when closed, the leaf cells hold in the water which prevents evaporation.  This conserves the existing water in the roots and leaves.

Binder clipsTo cover the plant take a lightweight fabric (a white or light colored sheet is ideal) and attach it to the plant during the most extreme heat.  I like to use black office clips on individual trees or shrubs.  Or use rocks to hold the fabric down if you are covering an entire bed.  Note:  This is also an excellent way to protect a plant from drought stress after transplanting.

(3)  In late summer when heat spikes up to 100 degrees you could add one additional watering per week.  Check your soil a few inches down with your hand.  If it’s still moist, watering is not the solution it’s the problem.

Established Plant Material:  Plants 2 or 3 years old are established plants.  If you have heavy clay soil you may need to water twice a week even in early summer.  Apply the water slow and for a long period of time.  If you have better draining soil, plantings may Cat watering plantonly need once a week watering.  All plants will respond to sudden change in temperature, for instance mild early summer weather interrupted by 3 days of intense heat, you will see leaf droop or slight wilting.  As soon as the intense heat retreats, the plants are fine and the leaves return to normal.  The only way you will know if they need additional watering over and above your typical practice is if you check the soil.  Remember, too much moisture and too much heat equals root rot.  Remember first rule, do no harm.

 

Hydrangea Pruning Made Simple

Spring Hydrangea Pruning

A lot of my clients have asked me to help them with pruning their hydrangeas.

Hydrangea serrata 'Preziosa'

This blog addresses mophead hydrangea pruning.  Hydrangea pruning is simple and easy once you know the rules.  There is a link to a pruning video at the end of this blog produced by Cass Turnball of Plant Amnesty to help you feel more confident.  There are 5 kinds of hydrangeas.  This blog only addresses mophead hydrangea pruning.

 

Hydrangea serrata 'Preziosa'

Why prune hydrangea at all?

Why prune hydrangea plants at all?  Like most plants, pruned hydrangea shrubs will have a better shape so they look good regardless of the flowering aspect.  Many of us buy a hydrangea and think it will be 4’ x 4’.  Over time, many varieties will grow to 7’ tall.  It is very important to plant the right plant in the right place so you don’t have to be frustrated.  There are some varieties that are going to mature at and be easily kept in the 4’ to 5’ range.  We prune to achieve that height as well as a good shape.  If you have a variety that wants to be 7 or even 8 feet tall every year even with proper pruning, the best answer is to remove the plant and buy a variety whose size works for your garden.  Old Arts and Crafts homes with 6’ high foundations are perfect for the hydrangeas that are most cheerful at 7’.  They don’t work as well for homes with a 12” foundation or a small yard.Another reason we prune is to remove stems that no longer flower.

rabbit ears 2

Nicely pruned and open plant

We prune hydrangeas in early to mid March in the Pacific NW.  We start pruning our plants when they are about 3 years old or when you see the oldest stems are developing bark.  Remove the oldest woody canes.  On a young plant this might mean removing only 1 or 2 stems.  We remove dead stems and canes and we deadhead flowers back to the first lateral buds.  I think of these buds as rabbit ears.  I love this task.  I think it’s because I’m close to the ground and my soil smells good.  I typically see 2 colors of buds at this time.  The burgundy buds are just a bump on the stems.  The tiny green buds (the rabbit ears) are such a vivid green.  It says spring to me (and no it doesn’t rain every minute even in March).  These are days when a wool sweater and a down vest are perfect for comfort.

hydrangea 1 heads banner

Joy Creek Nursery Hydrangea Garden

There is more to the story about hydrangea pruning. Occasionally there are individual plants that didn’t read the rule book.  My garden coach client Mary followed the proper pruning techniques and she lost all her flowers for the year!!  AAACK!!  Her plants are 30 plus years old.  Since that debacle Mary only deadheads her plants, again just down to the first buds and she removes old woody stems.  Her plants always flower beautifully and are the focal point of her summer garden.  I’ve never had this happen to me but I’ve heard about it often enough from other professionals to know that some plants are probably genetically different than others.  If you don’t prune at all, your plants will get big and ungainly looking.  A build up of deadwood may diminish their flowering capacity.

For a detailed lesson on pruning mop head hydrangeas, see this video.

Winter Flowers Feed Bees

bee-id-1

Saving Bees? Feed them. Plan for flowering plants from early spring until mid-fall.    Don’t use any pesticides.  Then you don’t have to try to figure out if the claim that it won’t harm bees is true or not.

Honey Bees and Heather FarmWinter flowers feed bees.    It’s easier to provide flowers for bees in our cool early springs than you might think.  What we are learning about saving bees can be made very simple.  Feed them!  Use a diverse plant palette with flowers from early spring until mid-fall. Don’t use any pesticides and then you don’t have to try to figure out what is safe and what isn’t or who to trust.

I have always found summer easy  to provide a diverse collection of flowers for all kinds of bees but early spring requires thought and planning.   My beach house landscape on the Olympic Peninsula is a great example of a very low maintenance and bee friendly garden. The plants I list in this article are from my experiences there and from my landscape design practice here in Portland, Oregon.

Erica Darleyensis Mary Helen

Erica darleyensis ‘Mary Helen’

If you’ve read any of my blogs, heather comes up a lot.  I love to use heather in my personal landscape and for clients where we can create good drainage. By the way, I had to learn how to grow it well.  The fact that many varieties of spring heather feed bees at a critical time is a huge bonus to an already great plant.  Deer don’t bother it, and it’s a glorious and tough ground cover.  Spring heather, native plants and early flowering Spanish lavender feed bees in late winter and early spring. I start out with heather varieties that flower in late January and into early spring.  These plants Erica Carnea – spring heather not summer heather  – are especially great for our native bumble bees who are out and about earlier than honey bees.  The bumble bees can protect themselves from sudden changes in temperature by nestling down in the thick foliage if they get too cold. I’d use the word cuddle but my inner 5 year old who hated the heather at our  front walk because it was buzzing with bees . . .  won’t let me!   Heather provides a lot of nectar for the bees because of the hundreds of tiny flowers on each plant. The flowers are just the right depth for different sizes of bees.   Some tube like flowers are better for hummingbirds but the heather flower (which is a tiny little tube) is just right for bees.  Here are some early flowering spring heather varieties I like:

‘Bells Extra Special’
Foliage goes to a whiskey color with flecks of orange in the cold, the flowers are a strong purple red and best of all it’s only 4 inches high.  It spreads to about 16” wide January to May.  This short compact plant is unusual among the spring heather,  most are 6 to 8 inches high.

December Red
Clean dark green foliage with Cabernet red flowers – 8” high and spreading to 18” November to April.

Adrianne Duncan
Has a strong violet purple flower and is more compact than typical,  6” high by 18” spread.  It flowers later than Bells Extra Special.  I like to put these two together for foliage contrast.

Erica darleyensis ‘Mary Helen’
Sports an interesting gold bronze foliage in winter and lots of flower power in February to April. These plants are grown locally by Highland Heathers in Canby, Oregon.   This grower supplies retail nurseries, special plant sales such as HPSO Hortlandia spring plant sale and you can buy directly if you make an appointment. You won’t find these varieties at a big box store.  The common varieties get too big for most landscape situations and then you end up hacking at them and then they are ugly and out they go.

Three things to pay attention to for success with heathers

  1. Soil prep
  2. Proper watering
  3. Yearly Pruning

A lot of my other early spring flowering plants are Pacific NW natives.  Rubus spectabilis, Salmon Berry,  has a spectacular colorful spring flower with 75 to 100 stamens which will keep bees busy for a long time.  This flower 220px-Rubus_spectabilis_1855calls the early bumble bees by the droves.  This shrub has thorns and needs a bit of room so think first and plant second.  Our Oregon grape,  Mahonia aquifolium, my evergreen huckleberry, Vaccinium ovatum, and the hot pink red flowering current edge the light woods around the house and provide for the various local bees.   Some people don’t like Oregon grape because the leaves can get winter damage and have ratty looking leaves by early spring.  I say no problem, let them flower to provide for wildlife and then cut them down to the ground.  They will re leaf into glossy and good looking foliage for the rest of the year.

We know English lavender is great for bees in the summer.  Like heather, all lavender has hundreds of tiny flowers and is an abundant source for nectar.   Spanish lavender flowers much earlier than English lavender and provides for mid spring to early summer nectar. We need good drainage to be successful with with Spanish lavender but this often just means mounding up a few inches.   Don’t over water Spanish lavender.  I water mine once a month and am not sure it even needs that now that the plants are old.

Lavender at Joy Creek Nursery

Lavender at Joy Creek Nursery

lavandula winter bee

Lavandula stoechas ‘Winter Bee’

There is a newish variety called ‘Winter Bee’ grown by Blooming Nursery, a local wholesale grower. They claim it flowers 3 weeks earlier than other Spanish lavender and have named it accordingly,  Lavandula stoechas
‘Winter Bee’ PP #20,840.Up at my vacation house my Spanish lavender flowers in early April to mid summer.  I have seen flowers on them in March.  After the main flowering, I cut it back about 1/3rd and get another lovely hit of flowers in late summer into early fall. Here are three spring flowering Spanish lavender varieties I have grown: ‘Blueberry Ruffles‘, ‘Hazel, and ‘Mulberry Ruffle’s‘.  Blooming Nursery sells to many of the larger garden centers but don’t look for their plants at a box store; they won’t be there.

This unusual variety is compact and flowers earlier than most Spanish Lavender.

This unusual variety, ‘Mulberry Ruffles’, is compact and flowers earlier than most Spanish lavender.

Last of all, the best early flower for bees at our beach property isn’t what you would think of as a flower probably.  It has to be the huge old Oregon Big Leaf Maples down at the edge of the beach.  When they flower, the sound of bees is a low roar, I am not kidding.  My grandkids are a little nervous and tend to stay out of that area for a while.  Bees will earn respect if need be but otherwise I find them easy to get along with.  I do flinch when a bumble bee takes a dead run at me… and then I scold them for being bossy. There is enough room in the garden for everyone.

Lace Bugs on the Move in Oregon

Azalea lace bug is a new pest that has decided rhododendrons are on the menu as
well as azaleas. This seems like a big problem because azalea lace bug has multiple
hatchings in a season and can do a lot of damage. The old rhododendron lace bug only hatched once a year in the Pacific Northwest.

Azalea Lace Bug damage

Rhododendron leaves showing damage from azalea lace bug

Organic Control Methods

Systemic sprays and insecticides kill bees. It’s very important to use methods that don’t harm beneficial insects.  Since drought and sun stressed plants are more susceptible, one method is to give these plants better care.  Practically speaking, I would say irrigate even your old rhododendron trees that never seem to need  a drop. Water them once a week during hot summer days as a preventative measure. Preventative methods are best.  So far this spring, out of perhaps 60 gardens, I’ve only seen one garden that didn’t have these new pests.  Preventative methods I’m recommending are building up green lace wings in your garden preferably before you have the pest or when you see that you do have it and better watering.

Using green lace wings, a beneficial insect, is another effective way to combat lace bug.  You can purchase green lace wing larvae and apply them near your affected rhododendron, the idea is to build a population of green lace wings in your garden from March Biological in Sherwood, Oregon. Ladybug Indoor Gardens in Medford, Oregon can also be reached at: 541-618-4459541-618-4459.  Please note, green lace wings are pretty, they remind me of Tinker Bell, sort of.  Using the green lace wings does work, as my associate and friend Phil Thornburg, (Winterbloom) can attest.  It took about 3 years but his plants have fully recovered and he has a nice population of the lovely green lace wings in his gardens as a bonus.  Their latin name is Chrysopididae and you can look them up on Wikipedia for more details.

OSU Azalea Lacebug PDF file imageThe chemical sprays I have seen recommended for lace bug are harmful to beneficials such as honeybees.  My recommendations are purchase and apply green lace wings and irrigate azaleas and rhododendrons weekly in the summer.   This will allow us to wait until a honeybee friendly solution to help us protect our plants is found.

Azalea lace bugs are here to stay.

For more details, download the informative Oregon State University flyer.

Hydrangea Love

My Mom with Oliver, the Hydrangea

There are several lessons in this story for you, O gentle reader………..how to successfully transplant a shrub or tree in July heat……, how to prevent hot weather damage to your plants  when we have intense hot weather right on top of weeks of cool rain, (more critical if you agreed to have your garden on a fundraiser tour).  This will also work to restore plants in a container that you forgot to water???? ……………..these lessons all fit into this story.

The story:  My mom and dad planted and named the two Hydrangea by the back patio, Mary and Oliver.  Mary was beautiful no matter what but Oliver had troubles.  Every year in early summer, Oliver’s flowers would get crisped.  If they had planted Oliver a few feet closer to the covered patio there would be no problem and no story.   They planted Mary in the afternoon  shade of the patio but Oliver got the early afternoon sun in June and July. He was just not a super sun tolerant kind of guy.

He could handle the sun better once the leaves and petals had hardened off in July but in early June, while the leaves and petals were full of spring, freshly unfurled, a 100 degree day or two would toast all the new flowers on the plant.  So Oliver’s flowers would scorch and my parents would then over water Oliver trying to get some water back into his petals. They did not understand that once petals are scorched they stay that way. Oliver’s new flowers were fine but now the plant’s leaves looked terrible. Overwatering caused the leaves to wilt and yellow. Oliver was a mess.  I offered to come over and protect Oliver from them. The human Mary and Oliver had long since gone on so these were not really plants to my parents. but symbols of their dear friends.

So how did I do this?  My first solution was to water once a week and the second solution was to protect Oliver from intense sun.  My solution was time consuming mostly because I lived in NW Portland and my parents lived in Gladstone.  If I was expecting intense sun,  I would drive over, get out some binder clips, drape a white sheet over Oliver to cover all his leaves and flowers and then clip the sheet onto various large stems so it could not blow off.

Because the leaves were covered (this is science folks!) they held in the water rather than letting it go, this is called transpiration. Transpiration is part of the plants photosynthesis process with the sun.  See Wikipedia on photosynthesis.  Since the flower petals and leaves kept their water, they stayed cool enough and did not scorch. I would not leave the sheet on for more three days at a time so I didn’t have to go over there every single day, just when I knew it was going to be hot).

Whats important for you gentle reader is that this sheet trick is handy beyond belief for all kinds of things.  #1  best tip ever for transplanting a shrub in the summer…….keep it covered for 3 days and I mean immediatley or even during the digging of the plant.  Use it to protect flowering plants  if we have intense heat while the flower petals are still new and soft. Use this trick if you have had an irrigation boo boo and your plants in one area didn’t get any water and  have wilted.  Presto, sprinkle the leaves with water gently, water the plant and cover for a few days……..your plant will have a better chance of recovery.

Every generation loves hydrangeas, my parents loved theirs, I love them although confess I have none of my own down here on the floating river house, my step daughters would love to have them…..maybe I can fix that this year.  They also look mighty fine with ornamental grasses so not just for an old fashioned garden but could be used in more modern gardens if placed thoughtfully.