Garden Calendar

 Everything in its season.  Even though I have been waiting to get started working outdoors there are sometimes when I realize that I've forgotten to get something started on time.  So I've taken this opportunity to review some of the key activities that I do, or should do, to manage my landscape over the year.

WINTER

Planning

As the growing season winds down, winter is a good time to reflect on the past season and decide what to do in the coming year.  Every year I sketch out a plan for the vegetable garden so that I can keep track of what I'm planting and when.  I can refer back to these from previous years to keep track of crop rotation.  This way I can ensure that I don't keep planting tomatoes in the same place, for example.

This was my 2024 garden plan.  I made notations about planting dates,
particularly for the corn where I staggered planting dates over 6 weeks.

Seed Starting 

If you are planning on growing plants from seed, particularly native species, many of these require a pretreatment in order to germinate.  In many cases this is accomplished by storing the seed under moist, but not wet, conditions in the refrigerator for 30 to 60 days.  This is referred to as cold-moist stratification.  It is meant to simulated conditions that a seed would experience in the wild. Prairie Moon Nursery has a Germination Guide for all of the seeds that they sell.  

Winter sowing is another method that is gaining popularity.  This is essentially direct sowing of the seed in a potting mix early in winter and leaving these containers outside to experience near natural conditions and break dormancy. Some advantages of this method are that the seed is already in soil so that they will begin growing when they are ready and you don't need to mess with grow lights and temperatures after you sow your moist-stratified seed.  See this post on Winter sowing I did a while back.

Direct sowing in the garden is also an option but I've had poor luck with this since it requires a perfectly prepared seed bed and protection of predators (birds) to get a good level of germination success.

Big Projects

If you are thinking of having work done winter is that time to get with landscape professionals.  They will have more time to work with you on designing and planning your work than if you wait until the spring.

Invasive Species Management

Winter is also a good time to eliminate many invasive species from your landscape.  In my previous blog post I listed some of the invasive species that could be addressed in the colder months.  These are mostly woody vines and shrubs.  I've been making progress against garlic mustard and Japanese honeysuckle by doing spot treatments with glyphosate in late winter, when temperatures are above 40°F.

Soil Tests

Winter is a very good time for doing soil tests as long as the soils are workable and you can take a proper sample.  By getting the results back before planting season begins you can make any adjustments well ahead of when plants go in the ground.  Winter is a particularly good time for applying lime, if needed.  Melting snow and wet weather help the lime to slowly infiltrate and do it job neutralizing excess acidity and increasing calcium levels. It may take 2 months for an application of lime to be effective.  See this link to the University of Delaware's soil testing lab.  

SPRING

Invasives  

In spring, when the forsythias are starting to bloom, is an optimal time to treat lawns with preemergent herbicides to control crabgrass, but more importantly to me, Japanese stiltgrass.  The blooming forsythias are a sign that the soil has warmed enough (55°F) that warm season grasses, like stiltgrass and crabgrass are breaking dormancy.  I have been doing this pre-emergent treatment for x years and have nearly eliminated stiltgrass from my turf, and reduced the amount of seed flowing into the surrounding woods.  I use a degree-day tracker, like the one from Michigan State, to optimize the timing of the treatment.

Forsythia and pussy willow (Salix discolor)
blooming at the beginning of April 2023

March into early April presents a window of opportunity for treating lesser celindine, Ficaria verna.  April is also when garlic mustard is putting on a growth spurt and producing flowering stems.  This is a very good time to pull these plants as long as the soil is loose enough to allow removal a most of the roots.  (If plants are actually in bloom the flowering parts need to be disposed of, otherwise even though they have been uprooted, they may still go to seed.)  

Ticks

Another early spring activity on our wooded property is to put out 'tick tubes'.  These are tubes with cotton balls treated with 5-7% permethrin, by weight.  The idea is that white-footed mice collet these for use in their nests.  The permethrin will kill any tick larvae present on the mice, thus reducing the spread of Lyme disease.  I mark each location with a landscape marking flag so that I can check if any cotton was taken from that spot.  I repeat the placement of tubes in late September hoping that the mice will take them into their nests over the winter.  I make my own tubes, but they are also commercially available.

Pruning

Late-winter to early spring is the time to start pruning summer flowering shrubs and plants that bloom on new wood.  For me this is mostly smooth hydrangeas (Hydrangea arborescens and cultivars). Spring blooming plants, like Azaleas, hollies, and big-leaf hydrangeas, should not be pruned until after they bloom, otherwise you will be removing flowering buds.  Fruit bearing trees are usually pruned in the spring, however each species has it's own particular timing to get improved fruit yields.  Apples, for instance are best pruned in late winter, in part to minimize infection of the cuts.  Any broken, structurally compromised or diseased limbs should always be removed as soon as possible.

Berry bushes like blueberries and blackberries really benefit from early season pruning.  To get improved fruits from wild blackberry I cut side branches back to 5-8 living buds in early March.  Last year I did a post of some of the wild brambles I have here.  

The four arrows indicate locations for pruning cuts on this wild blackberry. 
You can see that now, at the end of February, leaf buds are already swelling.

Garden Clean-up

As we are learning more and more about how we can help nature flourish in our gardens the advise is that whenever possible delay cleaning up the garden debris from last season.  Many pollinators and beneficial insects are overwintering in the fallen plant materials.  I will refer you to two links for more information on the hows and whys of delayed clean up: Izel Plant Blog and Penn State Extension.  In short if you can wait until early May, you will be doing a lot to help native bees and other pollinators.  Exceptions to delayed clean-up include plant diseases that overwinter in the leaf litter and insect infestations.

No Mow May 

No Mow May was started in England as a push to provide early season pollinators with flowers that are common in English lawns.  Blindly adhering to a no-mow-May program in a country with so many diverse climates and types of lawns as the US is often inappropriate.  To be useful, the lawn or property in question needs to have a population of plants with early blooming flowers that the pollinator population likes.   Depending on the climate the appropriate time for suspending mowing could be as early as February or into the later part of May.  If you have a monoculture of Kentucky blue grass there is little benefit to pollinators in skipping a month of mowing, there is just nothing of benefit there for them.  If you have a diverse ‘lawn’ containing native weeds like violets, self-heal (Prunella vulgaris), fleabanes (Erigeron sp.), spring beauties (Claytonia virginica) and the like, then allowing those to come into bloom would have a positive effect.  If you really need to mow, take the effort to mow around the blooming plants until they are done.  Lawns can also be interplanted with spring bulbs.  While not native, very early bulbs like Crocus, Chionodoxa and Scilla can add interest to an early spring lawn.  These bulbs have usually completed their growth and blooming cycle by the time the need for mowing kicks in.

I have been allowing this patch of Philadelphia fleabane
to develop without mowing.  It reaches peak bloom
in mid-May.  I usually mow it down in early June
after it sets some seed. When not in bloom plants survive
as low-growing rosettes.  

My recent experience with letting the lawn grow out late April through May was an increase in ticks. We are surround by trees and woodland edge habitat which makes the tick problem worse due to the higher humidity environments.  From what I've read ticks will not survive under low humidity conditions, so an open dry lawn should not be as much of a problem.  This year I will maintain the edge habitats at a lower level and try to avoid the lawn flowers.

While there is the oft repeated advice to never cut more than one third of the length of the grass blade at a time, I rarely let that force me to cut the lawn before I’m ready.  I can’t say that I have ever noticed a problem by occasionally letting the lawn get too long between cuts.  In those cases when I do, the biggest problem is the long clippings left on top.  A mulching mower can help deal with that.  All these problems are magnified on the ‘perfect’ lawn, where any imperfection becomes blaringly obvious.  In a diverse, multispecies lawn imperfections blend into the mosaic of plant colors and textures.

Plant the garden

If you are starting vegetable plants from seed you'll want to get them stared about 6 weeks before planting time.  Read the individual seed packets for more precise instructions.  Spring ripening crops like lettuce, spinach and peas can go in early.  Summer crops like tomatoes and cucumbers go in no earlier than Mother's Day, but I often wait until late May for tomatoes, especially when it's a cold, damp spring.

Spring and Fall are the best times for planting perennials, shrubs and trees.  Cooler temperatures and normally moister conditions help plants settle in before the stress of summer heat kicks in.  Fall may be a bit better for trees since they will have longer for the roots to get established.

Even before planting in the garden soil, you can plant in containers.  The soil in these warms faster in the spring and you can get a head start whether it be vegetables or flowers.  I often plant seeds for spring crops like lettuce, Swiss chard and spinach in early April in pots on our deck that has a good Southern exposure.  

Cutting back

Often referred to as the Chelsea chop  wholesale pruning of many perennials is from mid-to late-spring.  The name was coined from the Chelsea Flower Show in the UK which occurs in mid-spring each year.  When timed properly this leads to more compact, bushier plants with more blooms.  Cutting perennials back generally delays blooming by a couple of weeks, and gives shorter bushier plants.  By cutting half of a mass of plants back at one time and the rest a couple of weeks later you can effectively increase the blooming time for that mass by a few weeks.  You can also enhance the height differences in a mass back staggering the timing of the cuts or cutting some shorter than others.  You should finish the cutting operations by the end of June at the latest to give plants a chance to reach maturity  before the bloom season comes to an end.

The arrows indicate the two levels to which I cut back these masses of
goldenrods and asters.  This will also reduce plants flopping onto the pool deck.

 SUMMER

Pruning

Spring blooming shrubs can be pruned after they have dropped their flowers. Surprisingly Rhododendrons can take severe rejuvenation pruning and bounce back after a year or two.  So if you have overgrown rhodies blocking views in front of a window you can cut them back to a few feet tall and they will put out new shoot along the remaining stems.  Pruning can be done as need though the summer, but that chore should be wrapped up by the end of August to allow any new growth to harden off before cold weather sets in.  

Maintain New Plantings

Any newly installed plants will need extra care, particularly water, their first year in the ground.  Water as needed.  If you have established plantings, particularly native species, in the right locations these can be allowed to go dormant when conditions are harsh.  They will bounce back when temperatures moderate and or rainfall returns.  The same can be said of a lawn.  An established lawn with cool season grasses will want to go dormant in the heat of summer, this is natural.  It will bounce back.  As the saying goes: "Never teach a pig to sing, it's a waste of your time and it annoys the pig" (Robert Heinlein).

Control Invasive Species

Removal of invasive plants either manually or with judicious use of herbicide can continue through the summer.  If you are pulling invasive plants be aware of any seed that are present or developing and bag these so as not to spread the seed to other areas.

Deadheading

If you want to get more blooms from annuals or perennials, deadheading spent blooms is the future.  This guide from Garden Gate Magazine has a list of 50 perennials and whether and how to deadhead.  Deadheading will reduce the amount of seed produced in the garden, so if providing food for wildlife is important you may want to refrain from deadheading, particularly toward the end of summer.  Also leaving some seed heads in place can add interesting structure in the garden through the winter months.

Enjoy

Summer, particularly August, is when the landscape is peaking and there is actually less work to do.  Enjoy it!

Coastal Maine Botanical Garden

FALL

Planting

Fall is another good time to do new plantings.  Weather is cooling and there is normally more rain.  Mid-fall is usually a better time for planting trees, as there is less heat stress and root growth will continue as long as soil temperatures are in the the 40's.  

Invasive Plants

Continue to remove invasive species, but as before, be aware of any seeds that are present.  Fall is a particularly good time to do herbicide treatments on invasive trees like Tree of Heaven, Ailanthus altissima.  At this time sap is flowing down to the roots and  techniques like 'hack and squirt'  are very effective at concentrating a small amount of herbicide where it will do the most 'good'.

Deer protection

Here in the Mid-Atlantic the end of October brings on deer rutting season.  While deer are always browsing on plants, rutting season  is extremely destructive to healthy,1-4 year-old trees and shrubs.  Male deer rub there antlers on the trunks of young trees to remove velvet from their horns, stripping bark and flattening trees in the process.  They also will get very aggressive in mating season and seem to destroy plants as a way of showing dominance.  Welded wire fencing, plastic tubing and tree wraps are all helpful tools to reduce damage.  These some of these measures should be removed in spring if they cause the tree trunk to overheat or restrict growth. Fencing, cages and repellent sprays are useful for discouraging feeding.  

Here I have a 4" drain pipe spiraled around a sweet bay magnolia. 
Deer had severely rubbed the bark as high as the arrow. 
This was 5 years ago and the tree has recovered.

Here I have used plastic fencing to protect the bark from rubbing.

Ticks, Act 2

As the weather cools white-footed mice collect material for their winter nests.  This is a time that I put out a second batch of tick tubes.  Since I've marked each one with a colored marking flag I can check to see if any cotton remains from earlier in the year.  If there is still cotton, it indicates that no mice gathered material from that location.  In that case I will find another spot nearby that looks like better mouse habitat.  

Lawn care/Clean-up

If you feel the need for fertilizing your lawn, fall is the best time for a single application of a slow release fertilizer.  The nutrients are delivered slowly and are taken up and stored in the roots preparing the grass for regrowth in the spring.  Rather that using fertilizer I prefer to mow any fallen leaves into the lawn using a mulching mower.   Another option for fallen leaves is to move them into the garden or other area where they can serve as habitat for overwintering insects.  See the information links under Spring clean-up, above.  There are many reasons for putting off fall clean-ups; however, exceptions to delayed clean-up include plant diseases that overwinter in the leaf litter and insect infestations.

Review

Review what worked and what didn't.  Write down some notes where you can find them again.  You might think you'll remember, but there's a good chance you won't.

Dealing with Invasives in the Winter

Fall and winter are good times to use herbicides to control invasives.  At this time it is easier to spot many invasive species because they often hold onto their leaves longer than native species and there is less likelihood of harming native species with any mis-directed herbicide.  However not all invasive species can be treated effectively during this period.  At their January meeting, Blue Ridge Prism, an organization based in Virginia to address the threat of invasive species and to restore native habitats, the topic was about which plants could be treated over the winter months. A recording of that meeting can be found at this link:  January Meeting.  For each species mentioned here there are links to Blue Ridge Prism's  Fact sheets .  These provide lots of information each species including how to identify them and others species that may look similar.

One of the most obvious targets for winter actions are invasive vines growing up trees.  These include  English ivy, Hedera helix, and winter creeper, Euonymus fortunii.  At a minimum, these vines should be cut at the base of the tree and again a few inches to a foot or so up to create a gap.  If possible the lower stump of the vine should be treated with a 50% dilution of a recommended herbicide (e.g., 20% solution of glyphosate) to kill the roots.  This is referred to as the cut stump treatment.  The remaining vines in the tree should be left in place to slowly die.  Attempting removal can damage the tree and/or injure folks on the ground with falling debris.  Be observant when cutting the vines, wintercreeper vines especially are good at hiding in the furrows of the bark of trees. 

This tree has surrendered tp English Ivy.  The added weight
 can cause limbs to break, particularly with
accumulated snow and ice in winter.

These trees have winter creeper euonymus climbing up.  Winter creeper
sends out longer branches than English ivy.  These branches will bear
flowers resulting in the spread of this invasive species. 
Note that both of these vines have been 'deer pruned',
 but doesn't keep them from climbing.

For plants growing along the ground, these evergreen vines can also be treated with foliar sprays in winter, though not with 100% success.  Digging when the ground is soft and moist is quite effective at any time of year.

While not expressly discussed, Japanese honeysuckle, Lonicera japonica, vines cane also be treated in late fall and winter by either cut stump or foliar spray, if leaves are present.

Winter foliar spraying of  Vinca (V. minor and major) was reported to be effective, though personally I have not seen satisfying results.  For small infestations hand pulling is very effective.  I find that using a rake to lift most of the stems followed by using a trowel to get out the rooted plants is pretty effective.  Many folks recommend cutting, mowing or weed whacking first, then, later, hitting the regrowth with a foliar herbicide.  In doing this one must be very careful about killing non-target plants.  (These herbicide treatments are likely to be during a time while desirable plants are actively growing as well.)

There is not much else growing around this patch of Vinca minor
(Periwinkle) in January so careful foliar spraying shouldn't damage other plants.

I do have several areas where vinca has escaped the beds and is moving into forested areas.  Later in February I will try an experiment with foliar spraying alone compared with string trimming + raking followed by a spray with glyphosate.  There are some natives in this area, such as white avens, so I don't want to wait too long before I get started on this.

Fall and winter are good times to treat garlic mustard, Allairia petiolata.  The leafy rosettes of overwintering plants are easy to spot treat with the appropriate herbicide when other plants are still dormant.  Treatments can be done when temperatures are above 40°F.  I've done treatments in November and February-March. In my opinion the treatments later in winter were more effective because the leaf litter had broken down more making the garlic mustard leaves easier to target.  See this link to an earlier blog post about my efforts to eliminate garlic mustard.

Here's some garlic mustard in November,  In a mild winter
 these leaves will remain active all season.  Around March
 they will begin a growth spurt and put up a flowering stalk.

Gill-over-the-ground or creeping Charlie, Glechoma hederacea, can be treated with foliar sprays in early winter before a hard frost, but these would be more effective in early fall while plants are moving nutrients to their roots.  By January  most of the leaves have fallen off so there is no good target for a foliar spray.  Multiple treatments will likely be necessary.  The advantage of winter spraying, again, is that there are few non-target species actively growing at that time.

For Autumn olive, Elaeagnus umbellata, Nandina, Nandina domestica, and Bradford pear, Pyrus calleryana (fall to early winter), cut stump, hack and spray or basal bark treatments are effective. Autumn olive and Nandina can be treated effectively through the fall and winter. Treatment is not so effective in early spring when sap is flowing upwards.  Bradford pear should be treated earlier, while sap is still flowing downwards to the roots.  Smaller plants can be cut close to the ground and immediately treated with a concentrated herbicide on the stump.  Larger specimens can be treated using basal bark treatments (herbicide in an oil carrier) or hack and squirt.

These autumn olive bushes are in full bloom with their sweetly scented
 flowers seen here in early May.  I eliminated both of these with the
cut stump method using glyphosate.

While some invasive species can be treated throughout the winter months, usually when temperatures are above 40°F, some require treatment in a more specific time period.  Mid-fall to early winter is a time in which sap is flowing from the upper parts down to the roots.  Herbicide treatments at this time will carry the active ingredients to where they will have the greatest effect.  As mentioned above Bradford pear and gill-over-the-ground should be treated earlier.  Tree-of-heaven and Asiatic bittersweet are also in this group.  

Tree-of-heaven, Ailanthus altissima, is best treated in early fall when the sap is following down to the roots using basal bark or hack and squirt methods.  Cutting the this tree down is not an effective means of control.  The response to being cut down is for it to put out many root sprouts, so even treating the stump with herbicide is not going to be effective. 

Italian arum, Arum italicum, does not have an effective approved herbicide so digging is currently the only effective means of removal.

Lesser Celandine, Ficaria verna, is a major problem in moist areas, particularly along streams.  These can look like violets when not in bloom.  Digging small infestations can be done all year but care must be taken to remove all the roots, tubers, and bulbils, as well as seeds, if present, to avoid recurrence or spreading of this species.  There is a very narrow window of opportunity (about 2 weeks) for effective foliar treatment with glyphosate.  This is in the March-April time frame shortly after the plants have started to bloom, but before full bloom is achieved.  In wetland areas so you need to use a herbicide approved for those places (e.g., Rodeo®). 

This photo of lesser celandine was taken in mid-April toward
the end of the herbicide application window. 
When not in bloom the leaves do look similar to many violets

Some General Comments

Make sure you can positively identify the target species.  Especially with shrubs.  You could always tag the plant of interest with florescent tape in the winter and come back to it when it's leafed out or in flower to do a positive ID.

If you don't wish to use herbicide treatment, winter is a good time for pull up plants at times when the ground is thawed and moist and plants can be easily removed.  Just be careful not to disperse any seeds associated with the plant that you are removing.

For most plants a form of glyphosate will work.  Check the links for specific guidelines for each species.  In general, I prefer glyphosate as it is not translocated in the soil to other plants and that which reaches the soil is broken down quickly by soil bacteria.  In all cases follow the herbicide label instructions.

Just to throw in my own two cents, I wanted to add two things.  First while there is nothing you can do with Japanese stiltgrass  in winter, early spring (when forsythisas are blooming) is when you can put down preemergent herbicides to help eliminate this from lawns and areas where you are not encouraging growth from seeds.  Check this post for details.

Second, winter is also a good time to treat Japanese barberry using a cut stump treatment.  It can be spotted by the few remaining red berries along the stems.  There is a native barberry but it's quite uncommon.  It differs from Japanese barberry in that it has spines in groups of three along it stem, rather than the singular spines on Japanese barberry.

Managing Invasives 2022

This is pretty typical of an 'invaded' tree with
Japanese honeysuckle and oriental bittersweet
 twining among its branches.

We’ve been on our central Maryland property for about 9 years now.  From day one we have been battling a slew of invasive species that were covering the ground and trees through the woodland landscape.  While we still have a ways to go I feel that we have made some good progress.  As I am getting ready to start another season managing the landscape I thought I would organize my plan around actions and timing, rather than looking at one species at a time. 

First 

My first activity for the year will be to treat any visible garlic mustard, Alliaria petiolata, with a 2% glyphosate spray.  I'll do this sometime in the middle of March, when the temperatures  will be above 40°F with no rain for a couple of days. I started doing this 2 years ago and it seems to have helped me get the upper hand.  Prior to that I had  been only been pulling up plants in mid-spring as they grew tall prior to blooming. This link to my post on garlic mustard control options describes winter spraying in more detail and shows some of the desirable native species that may be visible at that time.  It also summarizes control options throughout the year.  The timing is critical as it is before the spring ephemerals, like spring beauties and Dutchman's breeches begin to sprout.  This lowers the chances of harming native species.   

Here you can see what a small garlic mustard, Alliaria petiolata,
looks like in winter.  Indian mock strawberry, Potentilla indica,
is also green through the winter.  Unfortunately, that weed is not
 as sensitive to glyphosate as the garlic mustard. 
See this link for methods to manage it.

Second

Cutting woody invasives and vines and stump treating with 20% glyphosate can be done anytime of the year that the temperatures will be over 40°F for a few days in a row.  Winter is a good time to do this as it is easier to get to the base of many or these plants and there is less chance of getting the herbicide on desirable plants.  Particularly troublesome on my property are multiflora rose, Rosa multiflora, oriental bittersweet, Celastrus orbiculatus, Japanese honeysuckle, Lonicera japonica, and to a lesser extent Autumn olive, Eleagnus umbellata.  An excellent reference for managing invasives in the Mid-Atlantic region is Plant Invaders of Mid-Atlantic Natural Areas. 

In doing dormant season treatments it is critical to be able to distinguish friend and foe.  Below are some images of multiflora rose and other native species that it might be confused with.  

Here is multiflora rose in the winter.  Some distinguishing features are
its round olive green branches and its curved thorns.  The most
distinctive feature are the fringed stipules at the base of the petiole,
shown in the inset above.  It is the only species with this type of stipule.

 

Most native roses do not have green branches in
winter. Thorn shapes vary.  Here, swamp rose has
straight needle-like thorns.

Cat briar has bright green branches in winter
and it has straight almost pyramidal thorns.

Wild blackberry has smooth red stems in winter
armed with stiff red spines. Older branches
are square with indentions on each face.   

Black raspberry has red canes with somewhat smaller thorns. 
It is distinguished by the white bloom on the older branches 

You can read more about  dormant season treatment of multiflora rose at the link.  This technique is also effective on English ivy, Hedera helix.  Even if you don't use herbicides to treat the cut stumps, cutting vines climbing trees and over shrubs is helpful in controlling the spread of these invasives.  This is because many of these species are only able to bloom on vines that are elevated and/or exposed to plentiful sunlight.

Oriental bittersweet can twine against itself to get
stiffer and climb higher.  I cut these a while back
but left them long so I could easily find them. 
I'll cut them shorter and treat with glyphosate later.

This is typical of the damage that Japanese
 honeysuckle can do to a tree.  This vine can be
 recognized in winter in that it still has leaves and
 the older branches have shaggy bark.  

Third

Around the end of March I will use a brush cutter and mower to cut down last years growth of vines and undesired woody plants in the meadow and woodland edges.  The biggest problem in my meadow is wineberry, Rubus phoenicolasius. In addition to the wineberry there are the aforementioned multiflora rose, autumn olive, and oriental bittersweet.  

Spring mowing and pulling has been pretty effective at reducing wineberry in shady areas. This is a short-lived species and not deeply rooted so it is usually easy to pull up.  Cutting to the ground in spring seems to keep it from blooming, but it is still able to reproduce by it ability to put down roots wherever a branch touches the soil.   It is recommended that mowing/cutting should be done several times each season to be truly effective.  This is particularly true in sunnier areas where the cut plants can rebound quickly.  Oriental bittersweet can also resprout easily after being cut.

Wineberry is easily recognized by its dense
coating of stiff hairs mixed with red spines. 
While formidable in appearance these are
easily crushed with a gloved hand.

I will return about a month later and do a foliar spray on the wineberry sprouts. While burning is not considered an effective option of wineberry control I will test out targeted ‘cooking’ of individual crowns with my garden torch to see if that kills them in place.  (Standard burns do not selectively kill the wineberry, rather it clears out the competition and allows it to grow unhindered.

Fourth

At about the time that the forsythia is beginning to bloom is the time for me to get started on Japanese stiltgrass, Microstegium vinineum, control.  Stiltgrass has definitely been reduced in the lawn by use of a pre-emergent herbicide originally used for crabgrass control.  It should be applied when forsythia are beginning to bloom.  If you want to be more precise you can use a growing degree day tracker geared toward turf management. like GDD Tracker 4.0. The product I use contains only dithiopyr (Dimension™) and no added fertilizer.  Most of my lawn is fescue based and not that hungry for added nutrition.  This link lists some other preemergent products that have shown effectiveness against stiltgrass.  I wrote about my year long plan for controlling stiltgrass in this post.  In the woods pulling and weed whacking, particularly in late summer has reduced, but not eliminated the amount of stiltgrass.  As a result of thinning out the stiltgrass, I am seeing more native species filling in such as white avens and Virginia jumpseed.  I am also seeing an increase in perennial grasses (perhaps a Glyceria species) in areas where stiltgrass had dominated. 

In the sunny meadow stiltgrass has been harder to eliminate.  The preemergent has not been as effective on the rougher soil and I am hesitant to use it every year as it may negatively affect the growth of desirable plants from seed.  Summertime pulling and the addition of tough native grasses and forbs is helping to displace the stiltgrass.  Weed whacking close to the soil level in late summer as the stiltgrass is beginning to bloom is effective.  However this will also damage other desirable species.  The best method or methods to use depend on the situation in a given location. 

Rest of Year

Mid-spring is the time when I will be watch for the rapid growth of garlic mustard as it prepares to flower.  Pulling it out and leaving it in the sun to dry is my method of choice at that time.  

Late-July and August are the time for pulling out stiltgrass as it prepares to bloom.

So there appears to be an awful lot to do, but it is encouraging that I have seen some progress.  I realize that I am talking about using a lot of herbicide, but these treatments are targeted on the actual plants and done at a time that has little negative impact on native species.  In this battle I feel it is necessary to properly use all the tools that are available.  Another aspect of invasive species control, is limited resources, especially time.  It is better to do one area really well, then move on to the next, rather than doing a little bit everywhere.

I wish you all good luck as another growing season is upon us!