Archive for invasives

Garlic Mustard

Garlic mustard 2

The first year leaf of garlic mustard (typically called the leaf rosettes).

What is garlic mustard (Alliaria petiolata)?  This cool-season biennial’s leaves and stems emit the smell of garlic or onion when crushed.  Plants are 12 to 48 inches in height, and in their second year, produce numerous white flowers with four separate petals.  Garlic mustard is the only plant of this height in the woods with white flowers in May.  Hand pulling before flowering is recommended.  It is believed to have been brought to North America by European settlers for use in cooking and medicine.

Here is the link to a brochure created by the Oregon Department of Agriculture:

How does it spread?  This weed spreads exclusively by seed.  The plant exudes a toxin from its roots into the surrounding soil and kills off competing seeds (the allopathic substance actually prevents germination of any seeds except its own!).  It also stunts the growth of nearby plants.  English Ivy in all its evil glory can’t hold a candle to this marauder.  It’s clearing the way so this plant can take the next area over.

Why it’s bad, very bad:  The concern surrounding garlic mustard comes from its ability to aggressively invade a woodland community and displace the native plant community to include grasses, shrubs, perennials, and tree seedlings.

weed-clipart-A_Little_Girl_Pulling_Weeds_Royalty_Free_Clipart_Picture_081111-152171-530047How to remove it:  Mowing is not an effective control because plants will still bolt and seed.  Mowing spreads garlic mustard seed like wildfire – do not mow when seed pods are present (May through September).  Hand pulling the weed is easiest during early bolt (2nd year).  Difficult during rosette stage (first year) except for small patches.  Multiple years are needed to exhaust seed bank.  Pull at base to avoid breaking stem.  All pulled plants should be bagged and removed from site (seed will set and/or plant will  re-root).

Garlic mustard mature

Mature garlic mustard

If you must use chemicals, use a product that contains glyphosate or Tricloypr.  To avoid damaging native forbs, spray the rosette stage during late winter/early spring.  If not sure how to identify rosette stage, you can spray during flowering.  Fall application to the rosettes (after some rain evens so plants are growing again) may also be effective.  Sprays at height of summer will not do much.  Use aquatic formulations when spraying near any body of water.  A combination of chemical and hand pulling is very effective – pulling bolted plants and spraying right after pulling.

I am not suggesting growing it for cooking, but while eradicating it from your property, you could get even with it by making a very tasty pesto from the leaves.  Here’s just one recipe I found on line:

Treatment for Blackberry and Ivy – How To Get Rid Of It

Garden Tips for getting rid of Plant Invaders

The best time of year to treat blackberries and English ivy is coming right up… prepare now!

Blackberry Fruit

How can anything so sweet, be so evil?

Plan to treat invasive blackberry in September and early October. The reason for the specific timing is this: only in the fall will the plants pull an herbicide to the roots, thereby killing the entire plant. The rest of the year treatments are only partially effective. For greener garden practices that use less chemicals treat the plants only in the fall, and water your bad old blackberries well prior to treatment. In fact you could even fertilize them and pamper them for about two weeks…….and then treat them with an herbicide.

My long time client Pat Tangeman  is clearing a large area of her property. She bulldozed last winter and got rid of a decades old blackberry wilderness that had an extensive root system with many large stumps. However, even a bulldozer didn’t kill all the blackberries! Many came back this spring so she called me to problem solve and design a planting plan for the area.

The result:
This fall she will treat her remaining blackberries and will allow the herbicide to trans-locate to the roots to truly kill the plant. Then she will have the remainder of large roots dug out. Once this is done she can plant the new garden we designed together. Victory over the blackberry!

Another client in the Dunthorpe area is having her English ivy treated by professionals the first of September. She is utilizing the same techniques by doing the pre-watering and pampering herself. Once the invasive plants are dead we will be ready to place her new garden plants from her garden planting plan.

Not sure still when would be a good time? Need a professional hands on approach to help get you started? There are still a few appointments for Garden Coaching open in September and October. Winter is also a great time for making plans so you can have what you want instead of taking your precious time to care for a layout and plants you don’t like.