Hairy galinsoga

About

Hairy galinsoga is a low, bushy annual from Mexico and Central America that is a top weed of vegetable gardens in the Northeast and upper Midwest. It flowers within weeks of sprouting and can run through three or four generations in one summer.

Also called shaggy soldier, quickweed, galinsoga

How to identify it

Look for

Opposite, triangular to egg-shaped leaves have toothed edges, and the stems are very hairy. Tiny daisy flowers, about 1/4 inch across, have five small white (sometimes pinkish) ray petals with 3 teeth at the tip, spaced apart around a yellow center.

Look-alikes

Smallflower (smooth) galinsoga looks almost the same but has smooth or only lightly hairy stems.

Where it grows

Cultivated soil in vegetable gardens, flower beds and vegetable farms.

When

Sprouts from spring through summer and can flower 24 to 60 days after sprouting, so spring plants drop seed by early summer and more generations follow.

How it spreads

Seed (a medium plant averages around 40,000), plus broken stems that re-root in moist soil; few seeds live more than three years.

Most common in

What to do, gentlest first

Start at the top. Weed killers are a last step; always read and follow the label.

1. Weed every few weeks all summer Prevent

   Because it flowers so fast, hoe or cultivate every 3 to 4 weeks through the season so no generation gets to seed.

2. Pull the whole plant and take it out By hand

   Pull seedlings while tiny. Older plants tend to snap off at the base and regrow, so pull slowly or dig them.

   Pulled plants and stem pieces can re-root on moist soil; carry them out of the bed.

3. Keep seeds in the dark Barrier

   Seeds sprout mostly at the surface and hardly at all from 0.4 inch deep, so mulch that blocks light, or shallow cultivation that doesn't bring up new seed, helps a lot.

4. Burn down seedlings with a contact spray Organic spray

   Horticultural vinegar (acetic acid), fatty-acid soap, pelargonic acid or clove-oil sprays burn what they touch within hours. They work best on young seedlings in warm, sunny weather, and you will need to repeat, because they don't move into roots and bigger plants regrow.

   They kill any plant they touch, so shield crops. Strong vinegar can burn skin and eyes; wear goggles and gloves and follow the label.

5. Garden-labeled pre-emergent or spot spray Conventional spray

   Pre-emergents labeled for your bed, or a glyphosate spot spray on the weed only.

   Read and follow the label. Many lawn weed killers also kill or damage vegetables and flowers, so keep spray and drift off garden plants.

Uses, wildlife and pets

Pets

Not listed by the ASPCA.