Weeds and Problem Plants
Weeds and problem plants can be one of the largest challenges in growing food from home.
A weed is simply a plant in the wrong place, That you don't want growing where it is.
These are normally problem plants, such as invasives, Which spread rapidly and outcompete other plants nearby,
Or they could be Poisonous making them unsuitable to be grown near food
or they could cause other problems like stinging nettles or brambles, creating barriers you don't want.
This section will focus on The most common Weeds and Problem Plants in the UK, It will also grade them by how bad they are.
The grading system will go from Green to Yellow to Red In order of ascending severity.
Dandelion - Taraxacum officinalis
Dandelions can be a pain once established, They have very strong and deep root systems, That will regrow from even the smallest fragment left underground, They also produce hundreds of seed and grow very quickly, The reason I've graded them so low on this list is due to the fact that they are also very beneficial for pollinators being one of the earliest nectar sources,
and that the entire plant is edible.
Dandelions used to be seen as extremely beneficial, They are high in nutrients and are actually very good for you,
The leaves and root can be harvested and eaten, The flowers can be used to produce a type of vegan honey.
The root can be used to make coffee and the whole plant can be steeped to make tea.
Dandelions will primarily be a pain if they begin to grow within other plants, where they'll pop up within the foliage and jam their root between the rootstock of the other plant, which will cause growing problems for it, The best method for stopping this is to ensure you have a good healthy soil and then pull the danndelion when it is very small, as once established it becomes trickier to deal with. Where the plant is growing in pathways or cracks, applying boiling water is a good method of stopping it and simply reapply whenever it regrow and eventually it'll give up.
Green alkanet - Pentaglottis sempervirens
RHS guide here: https://www.rhs.org.uk/advice/profile?PID=1001
This blue forget-me-not is able to regenerate from its deep rootstock and also spreads and grows from seed easily, Quickly becoming widespread and outcompeting other nearby plants, The Control for this plant is simple however, Simply pull it up whenever it appears where it is not wanted, ensuring you get all fo the roots else it may regenerate. be sure not to add it to the compost heap if the mature plant has set seeds, otherwise the compost will grow the seeds when spread.
Herb bennet - Geum urbanum
RHS guide here: https://www.rhs.org.uk/Advice/profile?PID=1002
Herb Bennet is a plant which spreads rapidly from root fragments, Rhizomes and seeds being spread by people and animals.
The easiest method of dealing with this plant is to simply remove it be hand before it sets seed, ensuring all the root has been pulled or dug out to prevent regrowth.
Sticky Willie - Galium aperine
RHS guide here: https://www.rhs.org.uk/advice/profile?pid=974
Sticky willie is an annnual weed which spreads quite quickly through gardens and veg plots if not contested.
Each plant produces about 300-400 seeds and can stick to clothing and annimals to spread.
Luckily the entire plant is easy to pull up and as an annual won't regrow.
and BONUS the entire plant is edible, the leaves can be blanched and eaten and the seeds and roots can be used to make a coffee substitute.
Nettles - Urtica dioca
RHS Guide here: https://www.rhs.org.uk/advice/profile?PID=714
Nettles are hardy perennials, With stings that cause a reaction with skin, intended as a deterrent to pests.
Nettles spread quickly through their creeping roots and high seed spreading capabilities,
However they are also very beneficial to butterflies, bees and other pollinators.
They are also Edibile, with their Leaves being highly nutritious and have other uses including cordage and textiles, The stems can be broken open and the outer bar can be used to create strong cordage or thread.
Nettles can become a serious issue in vegetable gardens, but are quite easy to prevent, simply by digging out the plants when small and composting them. Nettles are however beneficial so if you have a space in a distant corner where you'd like a wildlife patch, nettles are a good option.
Rosebay Willowherb - Chamaenerion angustifolium
(Fireweed)
RHS Guide here: https://www.rhs.org.uk/advice/profile?PID=993
Rosebay willowherb is a good soource of nectar for pollinators but due to its ease of self seeding and vigorous growth can be a serious problem weed. It grows quickly, reaching up through the foliage of other plants, then setting seed and spreading all over the place due to its windborne seeds.It's also Rhizominous, Speading underground by specialised stems.
The good news is that this plant is easily identifiable and can be simply dug out repeatedly until gone due to its shallow root system.
Creeping Thistle - Cirsium arvense
image taken from wikipedia
RHS guide here: https://www.rhs.org.uk/advice/profile?PID=719
Creeping thistle spreads using lateral roots and through seeds that germinate quickly. It can quickly become a problem if left unchecked, However its control is straight foward, simply dig out the small plants whenever they appear, Don't compost them unless they are left to fully dry before adding them. Ensure you deal with it before it begins seeding too.
Horsetail - Equisetum arvense
RHS guide here: https://www.rhs.org.uk/advice/profile?PID=257
One of the Terrible Two garden weeds, This nightmare plant is a relic from prehistoric times, a seemingly immortal, superpowered plant which is the bane of gardeners across the globe.
It is a deep rooted perennial invasive weed, Which grows vigorously, crowding out competing plants. The Rhizomes of this plant can reach a whopping 2M deep, and can travel just as far, meaning if a neighbouring property has horsetail and refuses to try and deal with it, you effectively have Horsetail too. Due to these Rhizomes, It's almost impossible to dig it out, Pulling works to a certain extent but tyhe plant is bittle and snaps off before you'll get any decent root. the best method without chemicals is to just stay on top of it, keep pulling, and pulling and pulling and eventually it should give up. if the plant is travelling from a place you cannot reach however it's a futile battle. The plant is also essentially fireproof, so weed burners and boiling water pretty much just tickle it. Because the plant can regrow from fragments, Only ever pull horsetail unless you intend to dig very deep, excavate and seive the area for fragments, otherwise digging basically just makes the issue worse. Never add horsetail to your compost heaps. Glyphosate weedkiller works to some extend but takes several applications over a period of years to be rid of it.
Some good news however, the young shoots of horsetail can be eaten like asparagus, So instead of chucking them in the compost, Scran them instead.
Couch grass - Elymus repens
RHS guide here: https://www.rhs.org.uk/advice/profile?PID=283
This plant will be the primary pain in the rear for homegrown vegetable gardeners.
Its wiry, underground stems and creeping shoots pop up around garden plants and before long can take over a bed.
As a perennial weed thorough killing or eradication of the roots is necessary.
The main issue with this plant is just how fast it spreads and how effective it that it is,
The rhizomes spreads within the roots of other plants, making digging it out a serious task.
Never compost Couch grass, It can come back to bite you so easily that it's simply not worth the risk.
If you have good soils, Couch grass becomes easier to deal with as the roots can be pulled or forked out quite effectively, However in clay soils it's a nightmare to get rid of, requiring tonnes of digging and careful checking to ensure its all removed.
Hand weeding is best done in early spring on small plants.
Glyphosate will work on this plant but it's not recommended as we believe in organic principles.
Japanese Knotweed - Fallopia japonica
image taken from the RHS website
RHS Guide here: https://www.rhs.org.uk/advice/profile?pid=218
The second part of the Terrible Two of garden weeds.
Japanese knotweed is a nightmare. That's all there really is to say about it, Originally from japan where it lived in areas of volcanic activity and was routinely doused in lava, which it survived and thrive in those conditions, It was brought to the western world by plant hunters where this absolute beast of a plant quickly realised that nothing here could contend with it.
