Bull thistle is a biennial that can form large infestations, especially along roads and vacant fields. They bloom in mid to late summer and grow erect with spines on the leaves and stems. They are coarsely hairy on the upper side, contain softer, whitish hairs below and rose to reddish-purple flowers grow at the ends of the branches. Bull thistle reproduces by seed only. For optimum control, application prior to seed set is most effective. Apply a post-emergent herbicide in fall or early spring, when the thistle is in the seedling to rosette stage.
There are different types of crabgrass you can be on the lookout for:
Large crabgrass is a bunching-type grass featuring seed head spikelets in two to nine fingerlike branches along the stalk.
These perennial weeds are pansy-like flowers featuring five blue-violet, lilac or white petals that grows in bunches reaching 2-5 inches tall. Wild violets can quickly take over cool, shady, moist, and fertile soil. Eradicating these weeds can be difficult due to its aggressive growth and resistance to many herbicides. To control, apply a post-emergent broadleaf herbicide as soon as the violets reach the two-leaf stage of growth.
Common chickweed is a low, dense growing annual weed that has branching stems with small, white, star-like flowers and five deeply-notched petals. This winter annual germinates in late fall and will start flowering in the spring. It prefers moist, fertile, and partly shaded locations but may sprout seeds in dry soil. Chickweed will also appear in lawns with thin turf. Control it with pre-emergent herbicides in late summer or early fall to prevent seeds from germinating or use a post-emergence control and apply it to actively growing immature weeds in the fall. If spring application is made you may need more than one application. Keep in mind that herbicide effectiveness is reduced as weeds mature.
The broadleaf plantain is a perennial weed that has smaller leaves with a green leaf base. Blooming in spring to early summer, you will notice it adapts well to most sites, including drought tolerant conditions and thriving in overwatered soil. They can grow in heavy soils, sunny or shady areas and under very low mowing heights. Since these weeds reproduce readily by seed, they will require repeat applications of a post-emergent, broadleaf herbicide to effectively kill off large populations. To help manage broadleaf plantain aerate your soil, avoid overwatering, and using proper mow cut heights.
Annual bluegrass is an annual weed, just as the name suggests. It blends very well with fescue grasses due to its light green color. Its color, however, makes it stand out in dark green turf grasses and will typically form in clumps, so it’s easy to spot the culprit. Annual bluegrass seeds germinate in late summer as temperatures start falling below 70 degrees. It appears where overwatering occurs and/or there is poor draining soil. Since it produces most it its seed head in the spring, applying a pre-emergent herbicide prior to germination of the seedlings will prevent growth.
Ground ivy is a perennial with square stems that extend several feet and root at the leaf nodes. These weeds showcase rounded scalloped leaves and small funnel-shaped purple flowers that grow in clusters. Ground ivy prefers shady, moist areas of the lawn with poor fertility, and can tolerate low mowing heights. Fall is an excellent time to use a post-emergent herbicide to treat it. Applications in the spring (when it is in flower) is also a good time to get effective control.
The white floaties provide widespread dandelion populations since they fly far distances, especially if the wind is strong enough. In fact, successfully grown dandelion roots help your soil remain aerated. As the roots grow deeply, they reduce soil compaction by creating air and moisture pockets underground. As a result, other tender plant roots have a chance to move into the aerated soil for ample foliage and stem growth. The dandelion taproot also increases nutrients in the shallow topsoil by moving critical elements, like calcium, from the deeper ground regions. Overall, successful dandelion seeds and seedlings create a fertile environment for all plant growth.
Before the specialized seeds appear, dandelions generate a yellow to orange flower on a stem that can rise up to 18 inches from the ground. This flower appears bright and fluffy against its green background, but is not a large or particularly appealing blossom for insect attraction. Requiring no pollinators, dandelions are self-pollinating and often change from flower to seed head over several days. This rapid seeding ability makes dandelions extremely successful at populating a widespread area — gardeners cannot keep up with the constant growth.
Because many dandelions find a good growing location in lawn areas, wind gusts often disperse the seed parachutes throughout the area. The umbrella hairs lift the seed from the head and float along the breeze. The extremely lightweight seed can float as far as the wind allows. Once dropped into another soil location, these seeds do not have extensive dormant periods like other plant species. In fact, the seed germinates quickly to establish itself in the new location before plant competition takes over for natural resources, such as moisture and sunlight.
Enjoying warm locations, dandelions (Taraxacum officinale) grow roots as deep as 15 feet into the soil, if they remain undisturbed. Often considered a weed in lawns and flowerbeds, these rapidly growing plants are hardy in U.S. Department of Agriculture plant hardiness zones 3 through10. The white floaties that the dandelion produces are specialized seeds that are highly successful for widespread reproduction.
The white floaties originate from a densely packed seed head that resembles a fuzzy ball. If you look closely, each seed head has dozens of umbrella-like extensions. Located at the seed head’s center are the seeds — each seed has this umbrella structure attached to them. The umbrella’s canopy consists of hairs formed much like a chimney sweep brush. Combining both a tall stem and airy seed head, dandelions keep their seeds upright and available to wind vectors for successful distribution in the region.
Writing professionally since 2010, Amy Rodriguez cultivates successful cacti, succulents, bulbs, carnivorous plants and orchids at home. With an electronics degree and more than 10 years of experience, she applies her love of gadgets to the gardening world as she continues her education through college classes and gardening activities.
A non-selective herbicide can be used to kill these weeds. Because of their voracious growth, it’s best to treat them with the chemical before the flowers have bloomed and the seeds are beginning to spread.
The root system and hearty growth of Japanese knotweed can damage your home’s concrete foundations, driveways, walkways, and retaining walls.
Lo and behold, the plant that is so beautiful and produces a treat that is consumed by the bucket at baseball games is actually a weed. Sorry to be the bearer of bad news.
Weed Control Methods
However, if you feel that a chemical alternative is your best option, then several quality pre and post-emergent products are commercially available to purchase. It’s advised that you use a pre-emergent product and prevent this weed from showing up on your lawn. Because once it spreads, it becomes challenging to contain.
Chemically, because of the likelihood that the daisy will appear alongside desired vegetation, make sure to use a selective herbicide for broadleaf weeds. If a non-selective herbicide is used, make sure to take proper precautions to prevent overspray onto your flowers and other plants.
Dandelions are most commonly found growing in lawns amongst the grass but can be found in gardens and flower beds if the conditions are appropriate.
This perennial broadleaf weed is a member of the mint family and can be found in lawns and gardens with a wide variety of growing conditions. The selfheal has leaves that are oval with slightly scalloped edges. The surface of the leaves of this perennial weed can range from smooth to slightly hairy.