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By Diane Emerson

March, April, May
Vegetable and Flower Gardens

Slug Control

Lots of slug eggs (look like tapioca pearls) hatch in March, April, and May. Slugs feed best when it is damp and the temp is between 50-60 degrees F. These are the evenings to go on slug patrol, and put out your slug traps: boards raised 1 inch, overturned melon rinds, beer or sugar/yeast traps.

Disease and Weed Control
Prune out old canes in berry plantings; fortify the soil bed annually with an organic fertilizer blend or compost; spread deciduous wood chips or leaves (bagged back in the fall) as bed mulch. Pull weeds when they first start growing, while soil is moist and roots are short, before they go to seed.

Plant Selection
Buy plants that resist disease and ones that are native to this area. Native plants are less
susceptible to disease, and can handle our wet winters and dry summers with less stress. Native plants are also better for local wildlife including birds, butterflies and beneficial insects.

Bird Control
Hang bird netting in place over blueberries and raspberries. Repair existing netting.

Tent Caterpillars
Watch for tent caterpillar nests. If it looks like they may become a problem, prune the nests in the early morning or evening when the weather is cool. Immerse in a bucket of soapy water. If they are attacking your plants, spray Bacillus thuringiensis, (B.t.). But spray only on those plants being eaten by the tent caterpillars, as B.t will also kill butterfly caterpillars.


Organic Lawn Fertilizer

Fertilize if needed in May with organic, slow release fertilizer. Get a soil test if you suspect deficiencies. Note that you need 55°F soil temperature before organic lawn fertilizer really kicks in. So be patient.

For Lawns in Poor Condition

Aerate, over seed, and top-dress with 1/2 inch of organic compost. If shade is the problem, consider switching to a mix of shade-tolerant grass and groundcovers, or go completely to shade loving groundcovers.


Start mowing, about 2.5 to 3 inches high for most lawns, and leave the clippings for free fertilizer.

Eco-Turf Seed Planting

Eco-turf seed mixes come in many varieties. Many combine drought-tolerant low growing perennials such as miniature clover, yarrow, and Bellis perennis daisy with grass, so the lawn needs less mowing, less or no fertilizing, and less water. Pests are less of an issue, because you are no longer growing a monoculture of grass.

Spring planting of eco-turf seed mixes begins when soil (not air) temperatures have returned to 50 degrees or warmer. For Puget Sound, that usually means the middle of April. Here is one source for the seed mixes:

European Crane Fly Control

In spring, apply beneficial nematodes to the soil, once the soil temp has reached 55 degrees F. or greater. Turf must be kept irrigated to support the nematodes. Aeration and de-thatching in the spring (before applying nematodes or as a substitute) will also help decrease the crane fly population.

Fruit Trees

Holistic Fruit Tree Spray

Sustainable and organic, Michael Phillips’ recommendations in his book The Holistic Orchard have been successfully applied in Puget Sound. Learn more about this approach at Below are summaries of The Holistic Orchard spring schedule:


  • Chip tree prunings and leave in the orchard for the benefit of soil fungi. Any
    obviously-cankered wood (and thus a source of disease inoculum) should be 
    removed from the site.

  • Finish any compost spreading not completed in late fall. Spread deciduous wood 
    chip mulch in haphazard fashion.

  • Plant new trees as early as possible, if you didn’t plant in the fall.

  • Boron needs are met with a sprinkle of Borax every few years. Most other 
    micronutrient shortcomings can be corrected by good compost habits and using 
    seaweed in tank mixes when spraying.

  • Remove any spiral trunk guards used on young trees.


Week of Quarter-inch Green
1st holistic fruit tree spring spray (liquid fish, pure neem oil, effective microbes) at double rate aimed at ground, trunk, and branch structure. Stone fruit growers can initiate the holistic sprays as much as two weeks earlier than apple timing. You can learn more about the holistic fruit tree spray and its ingredients here:

Week of Buds Turning Pink
2nd holistic spring spray aimed at unfurling buds, trunk, and branch structure. A good
amount of run-off should reach the ground as well.


  • Cut down wild fruit trees spotted in bloom within a hundred yards of orchard to

prevent pest migration to your trees. The exceptions here are those trap trees
managed (i.e., pruned at this time) as an "alternative home" for insects put off by
repellent strategies.

  • Hang pheromone wing traps for monitoring moth presence (pheromones are

species specific) and timing of first generation egg hatch, so you can know exactly
when to begin specific control measures.

Week of Petal Fall

  • 3rd holistic spring spray aimed at leaf canopy and developing fruitlets.

  • Begin mowing of green understory (preferably with a sickle bar and/or scythe) and
    pile resulting mulch thickly under trees around the dripline.


First Cover (7-10 days after petal fall)
4th holistic spring spray (liquid fish, pure neem oil, effective microbes) aimed at leaf
canopy and developing fruitlets. The fish will help meristem development for return bloom, neem stimulates immune function and hinders moths, microbes are biological
reinforcement for the summer ahead. Add horsetail and nettle teas as well to this brew.

After First Cover
Continue to spray the Basic Holistic Organic Spray Mixture every two weeks through May.
Codling Moth in the Holistic Orchard
Spray for first generation codling moth if codling moth is a problem in your orchard.
Options include Bt, spinosad, and granulosis virus; any of which can be tank mixed with
fish oil as a UV inhibitor and molasses as a feeding attractant. Growers may rely on parasite control and cardboard banding if high moth pressure has been abated previously.

The most accurate method to determine timing is degree day tracking, Learn more about
codling moth and degree day tracking here:


If you don’t want to use degree day tracking, you can monitor fruit in the trees to detect the beginning of egg hatch. Starting three to four weeks after bloom, check fruit at least twice a week looking for the first “stings,” or tiny mounds of reddish-brown frass about 1/16 inch in diameter. If you scrape the frass away you will see the tiny entry hole where the newly hatched larvae has just entered the fruit. Be sure to examine the fruit where it touches another fruit, as this is a common place to find an entry hole. Spray the tree as soon as you see the first sting; however, but first remove any fruit with stings from the tree, as the spray won’t kill any larva that already have entered the fruit.\

Learn more about codling moth here:

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