Apple Maggot Update

We’ve had several customers call after noticing that their apples (or pears) have apple maggot in them this year. The most asked question is, “What can I do now to prevent this from happening next year?”

We’ve posted in the past how to time sprays for apple maggot. Unfortunately, if you’re using organic controls, it only takes being a day off to have some damage occur. What most orchardists want is to minimize the amount of maggots every year.

Possible maggot fly ‘stings’

First, do you have maggots in the fruit? Some of the fruit on the tree may have black or brownish spots dimpling the surface. These definitely could mark the site an egg was laid and a larvae (maggot) hatched and entered the fruit. The picture here is pretty heavily ‘stung’, and some of the spots look like there are holes through the skin.

Cut open the fruit and look for larval trails. The maggot itself is quite small, but as it munches its way through the apple, the trails turn brown, discoloring the flesh.

Strategies for the home orchardist who finds apples with maggots, SANITATION:

  • Pick up all fruit as it falls- do not let it stay on the ground!
  • Feed the fallen fruit to cows, pigs, or throw in the garbage.
  • Do not compost (unless you cook it first). The larvae can survive home compost temperatures.
  • If you have chickens or guinea fowl, consider letting them forage under your apple trees. Pigs can also be pastured just after harvest under the trees to clean up (with care, they can damage the trees if left there after the fruit is gone).
  • Flame weeding under your trees in fall and early spring can help reduce the overwintering larvae population.

Apple maggot on sticky trap

Next spring, hang traps by early July, and check every couple of days for adult flies. Use this in conjunction with the models to time spraying.

After spraying, if you continue to get additional flies on the traps, you may need to spray again. For most home orchards, sanitation plus one or two sprays will control most of the maggot problems.

If you have neighbors with trees, consider talking to them about controlling apple maggot. The flies do not respect property lines!


Don’t forget to save the date! October 7 & 8 is our annual Fall Fruit Festival!

European Pear Harvesting

We’ve posted before about timing harvest of pears and apples, how to tell when they are ripe, when to pick, and how to store. As summer ends and fall begins, we are ramping up the harvest of pears and apples at Cloud Mountain.

Every year, we are asked how to tell if pears are ready to pick. European pears ripen from the core out to the skin, and if you wait until the pears are yellow and slightly soft to touch, they are rotten and overripe at the core. How to tell?

Clues to look for:

  • Have a couple of pears dropped? Probably time to test by picking a couple.
  • Has the skin color shifted from really green towards yellow?
  • Can you lift a pear and have the stem cleanly break from the spur? Time to pick!

Early ripening European pears, including Ubileen, Red Clapps, Bartlett, are probably ready now, if not past. If you have one of these varieties, go out and check it! Rescue and Orcas will probably be ripe in a soon- look at them now so you don’t miss the harvest window.

All of these early pears are great for eating, canning, drying, and preserves. They will only store a couple of weeks in refrigeration.

One of our favorite pear preserves recipe:

Ginger-Pear Preserves

9 cups peeled, cubed pears (about 2 ½ lbs)
2 thinly sliced, seeded lemons
6 cups sugar
1/3 cup chopped fresh ginger

Combine pears, lemons, ginger and sugar and let stand in refrigerator at least 12 hours or
overnight. The next day, bring the mixture to a boil, uncovered, over high heat. Reduce
heat and simmer until thick (1 to 1 ½ hours), stirring occasionally. Ladle into sterilized
jars, seal, and process 10 minutes in a boiling water bath. Makes 6-8 8 oz. jars.

How We Graft Japanese Maples at Cloud Mountain Farm Center

In our last blog post, we talked about Japanese maple propagation in general and why we graft, and today we will lay out the steps that we use in our grafting program.  With a few basic tools, a little bit of plant material, and a good bit of patience, you can build a Japanese maple collection with your own two hands.

Any plant propagation, grafting included, begins months before you actually make any cuts. This means you need to think about keeping your stock plants hydrated, properly fertilized, and free of pests the entire season leading up to grafting day.  In our area of Northwest Washington, grafting day usually comes in late July and goes into August.  It depends on the variety and the growing conditions, but you are waiting for the new wood on the mother plant to harden off; the wood should feel firm as opposed to tender and whippy. Next we’ll line out the steps…

First grab your materials:

• Acer palmatum rootstock (you did buy a rootstock right?), roughly pencil thickness

• Grafting knife (absolutely razor sharp, nothing less will do)

• Budding strips (or some other tying material)

• Grafting wax

• Plastic bag and labeling material

Next harvest your budwood:

• Collect budwood in cool morning hours, and keep it shaded during collection

• Choose straight shoots from this year’s wood…ideally the diameter of the budwood is ½ to 1/3 the diameter of the rootstock.  Good budsticks are usually between 6” and 12”.

• Snip off all leaves but leave a small stub of petiole (the leaf stem)

• Store budwood immediately in a plastic bag with a light spritz of water.  If not grafting   immediately, store the bag in the refrigerator for up to a day.

Then make the cuts:

• Sanitize all cuttings tools

• We use a side veneer graft .  Make the cut in the rootstock first and then cut your scion to match in both width and length.  The goal is to align both cambium layers perfectly on the sides and the tip.

• Be safe and protect your fingers! This can be a dangerous cut since the blade is moving toward your body.

• Place the scion piece into the rootstock cut and then wrap tightly with a budding strip.  The goal here is to cover all cut surfaces to prevent desiccation and to provide clamping pressure and achieve good contact between the two mating surfaces.

• Place a dab of grafting wax at the top of the cut to prevent moisture from pooling at the top of the graft.

• We put our new grafts into a misted area (1 second every 10 minutes) of a shaded greenhouse for two weeks.  Some people place a baggie over the entire plant.  The idea is to keep the plant and the new graft area in a high humidity environment during the early healing phase.

• After two weeks, we remove them from the mist but they remain in the greenhouse until the following spring.

If the graft fails at any point, it is usually obvious.  The scion wood will turn brown or black and look withered.  If the graft takes, it will remain bright, and buds will look plump and colorful.  If you are successful and the scion pushes growth the following spring, head back the rootstock to a few inches above the graft union and watch your new tree grow.

Grafting Japanese Maples

Summer heat is upon us and while many gardeners in Western Washington are simply trying to keep things alive during these hot dry months, we are in the heart of our propagation season.  Mid July is when the new wood of the Japanese maples begins to harden off, and that’s when the grafting begins.  We graft about 300 Japanese maples each year to replenish our stock, and the tiny plants that are propagated today may not reach the sales yard for five years or more…a testament to the time it takes to grow a beautiful, mature specimen.

But why go through the trouble of grafting at all? Why don’t we just germinate a seed, or take a cutting?

While seedlings may indeed produce beautiful trees, they won’t produce exact replicas of the variety that we are trying to propagate because the sexual reproduction that leads to seed formation mixes up the genes.  The seedling may be “better” or may be “worse,” but it is genetically distinct and therefore no longer the same as its mother tree.

And while cuttings, a form of asexual reproduction, would produce the clone we are trying to recreate, maples are known to be very difficult to root.  Therefore the easiest, most convenient way to propagate maple varietals ends up being via graft.  But “easy” and “convenient” are certainly not the first two words that come to mind when we discuss grafting of Japanese maples.


We use a side veneer graft, which in and of itself is not too complicated, but the wood of Japanese maples can prove difficult to work with.  It is brittle, and often very small, and sometimes filled with many nodes that make for challenging knife work.  If a good match can be made, and you can keep the young graft from desiccating during our 90 degree heat, then you have a pretty good chance of success.

Japanese maples are one of the most varied plant groups in our region, and each variety has its own distinct beauty.  Some are known for striking fall color, some for their winter form.  Others have incredible foliage owing to the shape or venation of the leaves.  Most tolerate sun, and all will do well in the shade, and there are a wide array of sizes to fit into most any space in the garden.

We currently have 69 different varieties available, and each year we add a few more to our collection.  We invite you to come see us and take a stroll through our gardens and the stock plants in our greenhouses to see which one catches your eye.

Shop available Japanese maples at Cloud Mountain Farm Center Nursery.

Apple Maggot Timing

People have starting asking us about when to spray for apple maggot. This is a complex pest to control in orchards and home gardens, so it is a good idea to understand its life cycle.

Adult apple maggot fly, 1/4″ long

Apple maggot, Rhagoletis pomonella, is a small sawfly that lays its eggs on developing fruit, most commonly apples, but also occasionally on pears and quince. The larvae eat their way through the flesh of the fruit as it ripens, often causing it to rot on the tree. (This is different than the damage caused by codling moth, which tunnels straight for the core, leaving much of the fruit still usable). The fruit infested with apple maggot will then drop to the orchard floor, where the larvae will leave the fruit to pupate in the ground.

Apple maggot can be a challenge to control in the orchard. One good method for the homeowner who only has a few trees is to apply maggot barriers. This nylon barriers should be on your fruit now, hiding it from the flies when they emerge and start looking for laying sites.

Another preventative method that works in larger orchards is to spray with a product called Surround. This is finely ground kaolin clay, and it also works to “hide” the trees from the pest. It must be applied before the flies start laying eggs, and it will turn your trees gray to white. It is not an easy product to find, but it can be ordered online. It must be reapplied after rain.

Apple Maggot Trap

You can also use insecticides such as spinosad to control the pest. You need to time the sprays carefully. The flies begin emerging from the soil in early summer. Like for codling moth, scientist have developed models that can predict the timing of the emerging flies. Right now, the models are predicting the first fly emergence in late July. But the best way to monitor for the flies is to put up sticky traps and check them frequently for the flies. You can buy red sticky traps that look like apples, or use yellow cards with an attractant. Check them frequently, and spray when adult flies are present.

If you have had very light apple maggot pressure in the past, you can put up three traps per tree, and try to trap most or all of the flies.



Thinning Season

We’ve posted on this topic before, but it is worth saying again how important it is to thin the fruit on your fruit trees. Typically, most trees set much more fruit each spring than they have the energy to ripen. By thinning the fruit while it is small, you direct the tree’s energy into the remaining fruit. It often comes down to quantity verses quality. By removing some of the quantity of fruit, you increase the quality.

Young trees especially should be thinned heavily. Remove all the fruit from the last 8″-12″ of branch. This will keep the fruit from pulling the branches down and causing the tree to become poorly shaped.

A cluster of apples set on one spur.

Same cluster after removing most of the apples

Another reason for thinning fruit is keeping the trees in regular annual bearing. Most fruit trees, left unthinned, will bear heavy crops one year, and light or no crops the next year. This is called biennial bearing, and is most common in apples, but also seen in pears and plums.

Unthinned Pear Cluster

Same Pear Cluster after thinning

Plum propped to prevent branches breaking.









With some fruit trees, the fruit set can be so heavy that the ripening fruit can break branches. This is a frequent recurrence in plum trees.

Plum and cherry trees can be thinned by removing fruit clusters from the undersides of the branches. This helps air circulation around the remaining fruit, and can help prevent the spread of brown rot.

Another way thinning now can help your trees? You can choose the best looking fruit on the tree to remain, and remove fruit that is misshapen or already damaged by insects and disease.

Summer Cover Crops

Most folks know that winter cover crops like rye and vetch can be a huge benefit to their soils. Winter cover crops benefit their crops by providing soil cover to prevent erosion, keep valuable nutrients cycling through the microbiome below the soil surface, suppress weeds, fix nitrogen for spring plantings, and provide a break in pest and disease cycles.  Once you’ve experienced the satisfaction and joy of the tilth that comes with good cover cropping, you’ll be interested in how you can take advantage of the smallest windows of downtime in your garden, whether it’s a half an acre, a single bed, or even just the spaces between established crops.

Spring Oats

We’ll take every chance we can to sneak some soil building in no matter the time of year.  This summer we have nice stands of spring oats and buckwheat.  The oats provide tremendous weed suppression from very early on in the season if you have the space and work when the soil temperature is too low for summer covers like buckwheat or sorghum sudan grass.  Oats also have the capacity to produce 10,000 lbs of dry matter per acre, which if you cut them at the right time, could also give you as much as 50 lbs of nitrogen (N) for a fall crop of brassicas, or clean ground for your garlic in October.  With oats planted early enough, you can let them grow to maturity, harvest the grain for your chickens or goats, then turn the oats you left in the field  with one quick pass of the tiller (or other soil stirring implement) and plant garlic as soon as the new stand of oats is killed by the first hard frost.  Throw some clover into that mix and you might have cover between your rows all winter long, with a little trickle of N every time you mow!

New buckwheat sowing

Buckwheat is a very fast-grower who isn’t related to anything else you might be cropping (unless you’re growing sweet potatoes). Buckwheat is one of the best cover crops to make phosphorous plant available.  Buckwheat’s root exudates have a way with phosphorus that few other plants share; in addition buckwheat is excellent for suppressing summer weeds and is a good source of nectar for pollinators and beneficial bugs.  Buckwheat can be mowed and turned in with just 6 weeks in peak season giving 2 to 3 tons of dry matter per acre.  It also makes a great nurse crop for slower growing summer grass covers such as sorghum sudangrass—just plant them both at the same time and mow the buckwheat at flowering to watch the sudangrass come thundering up behind for 4 or 5 tons of dry matter and the possibility for as much as 9 tons with fertile soil, adequate moisture, and multiple cuttings.

Crimson clover is another great cover most folks think of in winter mixes but in summer will establish more quickly and fully and can be mowed in pathways all summer to provide a N rich mulch every time you weed.

Codling Moth Update

Codling Moth

Hopefully many of you played with the codling moth tracking tool we posted about last month, and are tracking a weather station near you, in hopes of controlling codling moth this summer. Watching the weather has been tricky this year, with temperatures fluctuating between unseasonably cool to unseasonably warm. It has definitely been cooler overall than 2015 and 2016, with accumulation of Degree Days at the Bellingham Airport 23 days behind 2016.

But now we are close to the target accumulation of heat. Ideally, a control spray should go on at 525 DD. For the Bellingham Airport, that target will be reached on Wednesday or Thursday this week. Farther out in the county where it’s a little warmer, the target DDs will be reached Monday or Tuesday.

Takeaway, if you are planning on controlling codling moth by spraying this year, be ready this week!

Results of a Cold, Wet Spring

Peach Leaf Curl

Many fruit trees are starting to show the signs of a cold, wet spring. Our first indication of the weather showed up on peach trees, in the form of peach leaf curl. Established trees of leaf curl resistant varieties like Frost, Avalon Pride, and Betty showed much more leaf curl than normal this spring. Non-resistant varieties that were sprayed to control peach leaf curl also showed more curled leaves than normal.

What can you do at this point if your peach tree has leaf curl? You can remove the most infected leaves. The most important action is to make sure the tree is growing vigorously, and not subject to drought stress this summer.

Apple trees were the next to show their displeasure.  The past few weeks where the cold weather has alternated with warm days, powdery mildew has shown up in abundance. This fungal disease shows up as a gray to white film on the  stems and new foliage.  Scab is also very prevalent this spring.


The danger of these fungal diseases is twofold. Mildew can distort the new foliage significantly, and can also cause the wood to become ‘blind’, or lacking fruit buds. You can break off affected branch tips. A sulfur spray after breaking off can help keep new foliage from becoming infected. Most organic sprays will not cure mildew- this is one disease where prevention is the best action. Left to mature, the fungus can continue to spread through the tree. Affected leaves will not help support the tree’s growth.

Scab affects both the leaves and the fruit on both apples and pears. On the fruit, the fungus causes spots that become corky as the fruit matures. This damage is mostly cosmetic, although in severe cases, it can cause the fruit to crack. On the leaves, the fungus causes distortion and spotting. Affected leaves will drop early. Trees that experience this leaf drop year after year become stunted. On healthy trees, one year of scab

Scab infection on apples

infection is not critical. But because some of the foliage may drop early, it is important to ‘baby’ your trees and keep them growing vigorously this summer. Fertilize if you haven’t already, and make sure there is no drought stress this summer.

Even if you did it right, and timed a delayed dormant spray as the leaves were emerging, you may still see some scab. Because of the wet and cold, the scab cycle was much longer this spring than normal.

If your trees are experiencing any of these diseases this year, it becomes more critical to control them next spring, as it is the repeated infections that can stunt your trees.

High Tunnels- Training Tomatoes

At Cloud Mountain Farm Center, we grow about a thousand tomato plants each year in our high tunnels. All of the varieties we grow are indeterminate varieties, meaning they are varieties that continue to grow and produce over a long season, rather than setting all of the tomatoes at once.

One of the tomato tunnels at CMFC

Because of our cool summers and rainy falls, growing tomatoes inside high tunnels allows us to control the environment and get better production from our plants. We can lower the end walls and side walls of the tunnels to keep it warmer in late spring and in the fall, and we keep rain from spreading tomato blight diseases among the plants.

In order to maximize fruit and encourage early production and ripening, the tomatoes are planted at 12″ centers, and trained to only one stem each. Suckers from the leaf axils are removed on a regular basis, and the stem wound up a trellis string.

For the home gardener, planting tomatoes on 12″ centers could mean a lot of tomato plants. In a home tunnel, indeterminate tomatoes can be planted 18″-24″ apart and trained to 2 leaders rather than one. This means fewer plants to grow from seed or buy. The biggest difference is training an early, low sucker to be a second leader for the plant.

Two leaders trained on V string trellis

A home tunnel planted on staggered 18″ centers, trained to 2 leaders








By pruning your tomatoes, removing the excess foliage, you direct the plant’s energy into setting flowers and fruit, and ripening that fruit sooner.  You could also use 1 or 2 stout stakes and train leaders up those. There is also a product called a tomato spiral stake that works for single leader tomatoes.

These training methods are meant for indeterminate tomato varieties. There are a few “bush” type tomatoes, including some cherry and sauce varieties, that are determinate. These do not need the pruning and training that indeterminate types do, but your fruit will set and ripen all at once.