Controlling asparagus miners

Generally, parasitic wasps keep asparagus miners in check. If a heavy infestation occurs, remove the fern growth at the end of its season and throw it in the trash. Insecticides are not effective.


​Now you know.

Cut open the crown or below ground area of the plant, to see if sunken brown lesions or reddish flecks are present. Then, look closely at the roots. Infected plants will have reddish brown, elliptical lesions on the storage roots. Feeder roots will probably rotted off completely, though any remaining tendrils will have the same reddish brown discoloration seen elsewhere.


Disease lifecycle

Unfortunately, these fungi can survive in the soil indefinitely, and they are found pretty much everywhere. The disease is often spread as infected soil is moved from place to place on shoes, tools, and equipment. It can also be carried on seeds, which is why choosing reliable seed sources is so important. This disease can occur anywhere underground. Very often, insect feeding creates points of entry for these fungi. Asparagus miners are a common culprit.


Controlling Fusarium crown and root rot

Environmental conditions that keep plants healthy also improve their ability to prevent these fungi from entering in the first place, so avoid water stress and feed plants regularly with top dressings of aged compost. [Asparagus plants are very heavy feeders.]


Once a plant becomes infected, it should be removed completely, along with nearby soil, and disposed of in the trash. To reduce the chances of the disease taking hold in the first place, your asparagus plants should be rotated every five years and be sure to provide proper drainage.


Remember, perennial asparagus can provide you with many years of delicious spring and autumn spears, so don’t let these pathogens stop you from trying to grow your own!

Parsley - it’s not just for restaurants any more.


As a kid, I always turned a suspicious eye toward that sprig of greenery on my plate. My mother urged me to try it, so I did. Unfortunately, my young taste buds were not impressed. The mildly bitter bite of parsley was not my idea of delicious until many years later. Now that my taste buds are older and wiser, the refreshing tang of parsley adds a bright balance between flavors, cleanses the palette, and spices things up. If that weren’t reason enough to add parsley to a landscape, parsley packs one heck of a nutritional punch and, hey, it looks nice in the garden!

Parsley is a central Mediterranean plant, which means that it grows well in California, as long as it is protected from our scorching hot summers. Parsley makes an excellent shade garden or container plant. You can even grow it on your kitchen window sill for easy access and nice color if you have strong enough sunlight. 


Parsley is related to celeriac and celery, which explains its Latin name (Petroselinum crispum), which means ‘rock celery’, but it’s a heck of a lot easier to grow than celery. Parsley prefers well-drained soil that is kept moist, but my plants seem to grow under just about any conditions. In spite of my heavy clay soil, I have several parsley plants that thrive under roses, trees, and shrubs. Research has shown that parsley also repels asparagus beetles, making it a good companion to asparagus and tomato plants.


Growing parsley does require some patience if you are starting from seed. Seeds should be planted 1/2 inch deep, 6 inches apart, and they can take 4 to 6 weeks to germinate. Germination rates are pretty high, so growing parsley from seed is the most cost effective method. While you’re at it, plant some extras and give young plants to family and friends as gifts!


In tropical areas, flat-leafed and curly parsley are grown as annual herbs. In more temperate regions like ours, parsley is biennial. Biennial plants take two years to go from seed to seed, but some of my parsley plants keep on growing for another year or so. In addition to leaf parsley, there is a variety called Hamburg root parsley (P. crispum radicosum). Root parsley is grown for the taproot, which looks, cooks, and eats like a white carrot. (I may have to try that!)


Parsley plants allowed to go to seed provide habitat, pollen, and nectar to honey bees and many other beneficial insets, some swallowtail butterflies, and even goldfinches.You will probably also end up with many free, randomly placed parsley plants next year!


If flavor and looks weren’t reason enough to grow your own parsley, the CDC says it’s a nutritional gold mine. They ranked parsley at #8 as a food that reduces chronic diseases, such as cancer, coronary disease, and osteoporosis. To learn more, check out the U.S. Dept. of Agriculture’s nutritional analysis website that allows you to look up the nutritional value of pretty much any food. Just 10 sprigs of parsley provides 22% of the RDA for Vitamin C and 200% of Vitamin K.


It’s pretty. It’s durable. It’s good for you. And it tastes good.


Where’s your parsley planted?

European asparagus aphid description

Native to Eastern Europe and the Mediterranean region, European Asparagus Aphids (Brachycorynella asparagi) were first seen in the U.S. in 1969. They are now found throughout North America. Similar to the over 4,000 other varieties of aphid, the Asparagus Aphid is a tiny (1 mm), soft-bodied, powdery greenish-blue or grayish-green, pear-shaped insect with a pair of cornicles at the tail end of the abdomen. You can think of cornicles as tailpipes that spew a waxy substance in retaliation to attack. Some aphid varieties feature chromed-out monster truck cornicles, but the asparagus aphid is far more subtle and inconspicuous. It has short antennae and a relatively long cauda. The cauda is a tail-like appendage used to fling honeydew away from the insect’s body as it is excreted.


Ants and aphids

Ants are big fans of the honeydew excreted by aphids. So much so that ants will fight off aphid predators, groom aphids, and, I suspect, they might even bring aphids a latte every now and then, to keep them producing. It was the number of ants on my asparagus plants that drew my attention.


I planted my asparagus bed last fall using 1-year old crowns. Most of the crowns made it through our nonexistent winter and our scorching summer, but the ants were a clear indication that something was wrong. Closer inspection showed small, shiny black globules, which turned out to be egg clusters. I also noticed flat grey, oval bodies of immature aphids, upright green bodies of wingless adult females, and black winged adult males. The European asparagus aphid life cycle was in full swing in my asparagus patch and I should have noticed it a lot sooner. (That’s what happens when you go to Burning Man for three weeks at the height of the growing and harvesting season!)

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Aphid controls

One of the most common methods of controlling aphids is to use short, powerful bursts of water to displace the bugs from their host. This can work pretty well in most cases and it beats the heck out of using pesticides, which tend to kill off beneficial insects (predators and pollinators) along with the Bad Guys. Unfortunately, asparagus aphids damage your plants in a rather unique way that makes hoses an inadequate treatment. In addition to sucking sap from plant veins, these little buggers inject a toxin that reprograms the way the plant grows!


This reprogramming causes the spaces between leaves and twigs ("internodes") to become shorter, creating a tufted appearance called bonsai growth. This increases the number of the aphids’ favorite feeding sites. It can also delay bud break the next spring (which is struggle enough in our winter-less region). New shoots then emerge all at once, thinner and smaller than normal, draining the root system of desperately needed nutrients.


So, what’s an asparagus-loving gardener to do?

1. Identify the problem. Carefully and regularly monitor your plants for signs of damage or infestation. This let’s you know what you’re up against. Remember, finding out sooner is better than learning too late.
2. Know thy enemy. Female aphids hatch from eggs hidden in the soil anytime temperatures are warm enough, generally April to October, and they do not need males to reproduce!
3. Find a weak link in their life cycle. Asparagus aphids lay microscopic egg clusters that look like shiny black blobs to the naked eye. Eventually, those eggs fall from the plant and overwinter in the soil. Armed with this information, you can remove and destroy (burn) any infested stems before the eggs have a chance to overwinter hidden in the soil.
4. Promote natural predators. While garden supply stores are happy to sell biological controls, your best bet is to simply avoid using pesticides and to include plantings that attract and provide for beneficial bugs. Most beneficial adult parasitic wasps eat nectar and pollen from plants with shallow flowers, such as fennel, dill, yarrow, parsley, cilantro, mint, cosmos, marigolds, sunflower and chrysanthemums. These adults will then lay their eggs in soft-bodied garden pests, which will then hatch and, well, you get the picture….

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 ​So, go check on your asparagus plants and let me know what you see!