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How to Cut and Install Retaining Wall Topper Stones

Julie Day — Wed, 03 Mar 2010 23:03:19 +0000

Topper stones make a wall look finished but have to be cut to fit a curved wall.

How do I add square topper stones to a curved retaining wall? And how do I attach the topper stones so that they don’t get knocked off? -Paul

Those wedge-shaped stackable stones are great for building curved retaining walls, but once complete it leaves you with unsightly gaps. For a finished look, you can add topper stones, but it poses some challenges since:

Topper stones are usually square, not wedge-shaped, so if you want a smooth top you’ll need to cut them to fit the curve. If your curve is very gradual, you might be able to get away with spreading out the small gaps so they aren’t noticeable.
Topper stones are also a bit wider and lighter than the wall blocks, so it’s easy to kick them out of place or bump them with a lawn mower. I have topper stones on my wall, and I’m always knocking them loose and having to put them back.

Instead of my kick-and-replace method, there are better ways of finishing off your retaining wall! Try these tips.

Use a Masonry Saw

Retaining wall blocks can be cut using a masonry chisel and mallet, but for the topper stones you may want to spring for a diamond blade masonry saw such as the Edco Hardscape Saw. Similar to a wet tile saw, masonry saws make very clean, straight cuts that will give a nice finishing touch to your wall. Masonry saws can be rented at your local rental center – all you’ll need is an extension cord and a garden hose to provide lubricating water.

The bottom stones will be cut along the lines, and the top one will be left square.

How to Measure the Cut

If you enjoy geometry, you can cut each stone at an angle to curve along your wall. For a faster job that looks just as neat, try this approach:

Step 1: At the beginning of your wall, place stones #1 and #3 in their places. You’re going to be cutting both of these.
Step 2: Lay stone #2 on top of them, with the front corners lined up. You’re NOT going to be cutting this stone, you’re just using it as a cutting pattern.
Step 3: Draw lines on stones #1 and #3 where the top stone overlaps them.
Step 4: Cut stones #1 and #3 along your lines.
Step 5: Replace the stones on the wall, and now stone #2 should fit neatly between them.
Step 6: Now put stone #4 on top of stones #3 and #5, and repeat. The odd-numbered stones will be cut on both edges, and the even-numbered stones will be left uncut.

The back view shows the overlap of the stones and the cutting line being marked.

Adhere the Stones

Once your topper stones are cut and fit, you can keep them in place using masonry adhesive. Masonry adhesive usually comes in a tube for use with a caulk gun and should be available at your home improvement store. Examples include:

For a very solid wall, you can also use the adhesive to attach the stackable blocks themselves.

Further Information

How to Build a Stackable Block Retaining Wall

Why Aren’t the Flowers in My Garden Blooming?

Julie Day — Tue, 02 Mar 2010 22:47:46 +0000

All of a sudden, my flower garden, which is normally full of color all year, has turned green. Why aren’t my plants blooming? -Julie M.

It’s so frustrating to take good care of your plants and be rewarded with a lack of blooms! In order to diagnose exactly why a plant isn’t blooming, you really have to understand the individual plant itself. Many plants have particular needs that can affect their flowering. However, if your entire flower garden has stopped blooming, there might be something else going on.

Here are the main reasons why plants don’t bloom, and some things you can do about it.

Annuals

Annual plants typically bloom for most of the growing season. If they stop blooming, it may be caused by:

Overfeeding: Nitrogen promotes leaf and stem growth, so too much nitrogen results in green plants with no blooms. Even a balanced fertilizer with equal amounts of nitrogen, phosphorus, and potassium might have too much nitrogen for your flowering plants.

What to do: Water your plants really well to wash away some of the nitrogen. Stop using your current fertilizer and give your plants a few weeks’ rest before switching to one with little or no nitrogen and extra phosphorus. Fertilizers labeled as “bloom-boosting” usually have better proportions for flowering plants.
Heat: Some plants stop flowering when stressed by the heat, particularly if overnight temperatures rise too high.

What to do: There’s not much you can do for heat-stressed plants other than keeping them alive and healthy until the weather changes.

Cold: While cooler temperatures are often vital for the setting of flower buds, a dip too low can freeze the buds and cause a season without blooms.

What to do: Choose plants that are hardy in your climate, and protect tender plants from cold temperatures.
Light: The amount of sunlight is crucial to getting plants to bloom. Sun-loving plants won’t bloom in shade, and shade-loving plants have trouble in too much sun. Also, some plants are “photoperiodic,” which means they bloom in response to the change in the length of daylight as the seasons progress.

What to do: While you can’t change the seasons, you can make sure your garden is getting the amount of sunlight required by your particular plants. Check to see if trees or other plants have grown tall enough to shade your garden, and move plants to a different location if there’s not enough (or too much) sunlight.

Water: While all plants need water, some—particularly desert plants and highly drought-tolerant plants—slow or stop blooming when overwatered. On the other hand, water-loving plants can stop blooming during drought.

What to do: Check each plant’s individual water needs to make sure you’re not over or under watering.
Underfeeding: Container plants especially are vulnerable to nutrient depletion.

What to do: Amend your soil with compost and organic matter, and feed with a fertilizer lower in nitrogen and higher in phosphorus.

Perennials, Shrubs, and Trees

In addition to the above factors, perennials, bulbs, shrubs, and trees might be affected by:

Season: Most plants bloom during a particular season that can last days, weeks, or even months. For example, if your garden is full of spring-flowering plants, it will only be colorful in the spring.

What to do: Plant a variety of plants in your yard for year-round color.
Plant Age: Some plants don’t bloom until they’re mature enough, and many won’t bloom the first season after they’re moved or transplanted.

What to do: Allow time for plants to mature when young or after transplanting.
Pruning: Plants that bloom once per year can be affected by pruning that removes tiny flower buds. For example, camellias set buds for spring blooms several months earlier, so a late fall pruning can cut off next spring’s flowers.

What to do: Make sure to prune plants at the correct time for each type.

Alternate Flowering: Some flowering trees will spontaneously bloom very profusely one year, then take a year or two off.

What to do: This can happen naturally in some varieties, but in the future you can choose plants less prone to alternate flowering.
Complacency: Plants bloom in order to reproduce and survive, and older settled plants may be “too comfortable” to need to bloom. Sometimes you can encourage a shrub or tree to bloom by stressing it a little.

What to do: Try root pruning to encourage your plant to bloom.

Further Information

Why Plants Fail To Bloom (University of Vermont Extension Service)
‘New Dawn’ Rose Not Blooming
Perennial Flower Garden Basics
Deadheading Flowers (video)

How to Use Neem Oil in Your Garden

Julie Day — Mon, 22 Feb 2010 16:16:50 +0000

When I read about organic gardening, I see a lot of references to neem oil. What is it, and how do I use it in my garden? -Sherry

Neem oil is made from the seeds of the neem tree (Azadirachta indica), which is native to India. Since ancient times, the neem tree has been prized as a sacred remedy and important ingredient in Ayurvedic medicine. In the garden, neem boasts a powerful insecticidal ingredient, azadirachtin, which makes it a great organic choice for controlling a variety of problems.

Uses for Neem Oil

Neem oil can be used to treat a number of garden ailments, including:

Insects: Neem oil kills or repels many harmful insects and mites, including aphids, whiteflies, snails, nematodes, mealybugs, cabbage worms, gnats, moths, cockroaches, flies, termites, mosquitoes, and scale. It kills some bugs outright, attacks the larvae of others, and repels plant munchers with its bitter taste.
Fungus: Neem oil is also effective in preventing fungal diseases such as black spot, anthracnose, rust, and mildew.
Disease: As if that wasn’t enough, neem oil also battles viruses that can harm plants.

Advantages of Neem Oil

Neem oil is a popular choice in organic gardens because it is:

Nontoxic: As long as it isn’t sprayed directly on them, neem oil is nontoxic to beneficial garden insects such as predatory wasps, honeybees, earthworms, ants, spiders, ladybugs, and adult butterflies. Neem oil is considered nontoxic to humans, birds, and other animals as well (see below) and can be used on fruits, vegetables, and flowering plants.
Organic: Neem oil is plant based and easily available from organically grown neem trees.
Biodegradable: Neem oil breaks down quickly and leaves no lasting residue.

How To Apply Neem Oil

Neem oil concentrate is usually mixed with water and sprayed on both sides of plant leaves. Because oil and water tend to separate, you’ll need to keep your solution well stirred. You can also mix it with insecticidal soap for a double whammy. Neem oil is bottled in different concentrations, so follow the instructions on the package to get the right proportions of oil to water.

Other Uses for Neem Oil

If you’re concerned about the safety of neem oil compared to other products in your garden, consider that neem is often used as an ingredient in:

Cosmetics
Shampoos (including pet shampoos for flea/tick control)
Natural insect repellents
Alternative medical remedies for antiseptic, antiviral, antifungal, and anti-inflammatory uses

The only health cautions for neem oil relate to actual consumption of the oil, and garden use does not appear to pose any known health hazards. As with any chemical—organic or synthetic—use neem oil only in moderation when needed, and wash all veggies and plants thoroughly before eating.

Further Information

Material Fact Sheets: Neem (Cornell University)
Azadirachta indica: One Tree’s Arsenal Against Pests (Colorado State)

What Is the Proper Mowing Height for Grass in Your Yard?

Julie Day — Thu, 04 Feb 2010 17:19:15 +0000

How low–or high–should I cut the grass in my lawn? -Rasheem

The proper height for mowing your lawn depends on the type of grass, the season, and the growing conditions. For example, bentgrass can be mowed under ½-inch, while tall fescues should be 3-4 inches high. Choosing the correct mowing height is important since:

Proper mowing creates a low-maintenance, drought-tolerant lawn.
It discourages undesirable grasses and weeds while encouraging your chosen grass type. For example, mowing fescue higher will discourage Bermuda grass which is low-growing.

Pointers for Setting Mower Cutting Height

Shady grasses grow better if mowed a little higher.
Raise the blade to the top of the cutting range for your type of grass (see chart below) during drought conditions in summer to reduce the stress on your lawn.
Cut warm-season grasses at the lower end of the cutting range in early spring to remove dead blades.
In general, cool-season grasses do best when cut as high as possible.
Different varieties within the same grass type may vary as to the best cutting height, so try to identify the specific variety you have (such as ‘Zenith’ zoysia or ‘Empire’ zoysia), then check with a sod or seed supplier for cutting recommendations.

Recommended Mowing Heights for Lawn Grasses

The chart below gives general guidelines for grass cutting height.

Grass Type	Mowing Height
Bahia grass	2½” – 4”
Bentgrass	¼” – ¾”
Bermuda	½” – 2½”
Buffalograss	2” – 4”
Centipede	1” – 2 ½”
Fine fescue	2½” – 3”
Kentucky Bluegrass	1½” – 3½”
Ryegrass	1½” – 2 ½”
St. Augustine	1” – 3”
Tall fescue	2” – 4”
Zoysia	½” – 2”

Further Information

Making Mowing Easier
Proper Mowing Techniques
Choosing Grass For Your Climate
The Basic Grasses (Turfgrass Producers International)

What Can I Compost?

Julie Day — Fri, 29 Jan 2010 22:26:19 +0000

What can I put in my compost pile? -Beth

If your compost pile is heating up properly, you can put all kinds of things in there. Be sure that everything you put in your compost pile is in pieces smaller than 1-2 inches. Shredded and chopped items break down must faster than whole pieces.

Here’s a list of compostable items, including a few that might surprise you.

Yard and Garden Debris

Dead plants
Extra potting soil
Grass clippings
Leaves
Old cotton or leather gloves
Peat moss
Pine needles
Pruning debris, limbs, and branches
Rock dust
Sawdust
Seaweed
Straw and hay
Wood chips

Kitchen Scraps

Fresh or rotten produce including peelings, rinds, cores, stems, and leaves
Breads, grains, cereals, and flours
Canned fruits and veggies
Coffee grounds and paper filters
Corn cobs
Crackers and pasta
Egg shells
Fish bones and skins (if well buried)
Freezer-burned fruits and veggies
Ground-up animal bones
Herbs and spices
Gelatin
Jams and preserves
Milk, yogurt, and ice cream (although these may attract hungry animals)
Nut shells and husks

Paperboard (such as cereal and pasta boxes)
Popcorn
Rice
Seafood shells
Shredded paper towels and napkins
Soy products
Tea bags and loose tea
Toothpicks
Wine and beer
Cork wine corks
Wooden skewers

Household Waste

Compostable forks, cups, plates, etc (look for these in the store!)
Cotton balls
Cotton swabs (if made of paper)
Crumbs and dustpan contents
Crushed seashells
Dead bugs
Dried flowers and potpourri
Dryer lint
Dust bunnies
Felt
Fireplace ashes (in small amounts)
Floral arrangements
Hair clippings (also good in the garden as critter repellent)
Houseplant trimmings and old potting soil
Tissue

Leather
Loofah sponges
Matches
Nail clippings
Rope (natural fiber)
Shavings from your pencil sharpener
Vacuum bag dust
White glue and paste
Wool, linen and cotton
Wreaths, garland, and Christmas trees (real, not artificial)

Paper

Shred these paper items and add to your compost pile or recycle bin.

Business cards
Cardboard
Egg cartons
Envelopes (remove plastic windows)
Muffin cups
Newspaper
Office paper
Paper plates (unwaxed)
Paperboard (such as cereal boxes, toilet paper rolls, etc.)
Post-It Notes
Ticket stubs

Pet and Animal Waste

Dry pet food
Feathers
Manure from herbivores (cows, horses, rabbits, etc)
Pet hair
Wood chips from pet cages

Compost Cautions

These items should NOT be added to your compost pile:

Aluminum foil, plastic bags, and other inorganic packaging
Chemicals such as pesticides, herbicides, bleach, gasoline, and oils
Cooked foods

Bread, yes – package, no.

Diapers
Diseased plants
Glossy or heavily dyed paper
Grease and fat
Kitty litter
Manure from meat-eating animals (dogs, cats, humans)
Mayonnaise and peanut butter
Meat scraps
Particle board
Treated lumber
Whole bones

Further Information

Is It Safe to Use Pre-Emergent Weed Preventers Around Bulbs?

Julie Day — Mon, 25 Jan 2010 21:23:27 +0000

Is it safe to use pre-emergent herbicides (such as crabgrass preventer) around my established bulb beds? -Helen

The short answer is “sometimes,” because in gardening a simple question doesn’t always have a simple answer! Products that are labeled as “weed preventers” are usually pre-emergent herbicides, which work by stopping seeds from germinating, so it stands to reason that they shouldn’t affect established bulbs (especially dormant bulbs underground). However, that’s not always the case, as a product labeled “weed preventer” may have any number of active ingredients that affect weeds, seeds, and garden plants in different ways. Every product should be evaluated separately to make sure it’s safe.

Corn Gluten: The Organic Choice

Corn gluten meal is a popular organic choice for preventing weeds. Corn naturally produces a substance that suppresses the germination of competing seeds. In addition to its weed preventing properties, corn gluten is high in nitrogen and adds some organic matter to the soil – nature’s own “weed and feed!”

Sold under brand names such as Preen Organic Weed Preventer, corn gluten meal is considered safe for use around bulbs, shrubs, trees, and ornamental plants. In addition, it’s far less toxic than chemical herbicides.

Chemical Herbicides: Check the Label

As for commercial chemical weed preventers, you really need to read the label. Some are safe around all bulbs, some are safe only if you apply before the bulbs sprout, and others aren’t safe at all. Before applying, read the label (and do a little research) to make sure the product is safe.

Examples of common products include:

Surflan AS is safe around bulbs according to the product label.
Scotts Turfbuilder with Halts Crabgrass Preventer is considered safe as long as it is applied before bulbs sprout.
Trifluralin, the active ingredient in Preen Garden Weed Preventer, is also listed as safe around bulbs.
On the other hand, Preen Lawn Crabgrass Preventer, isn’t recommended for use around bulbs. In this case, the product label wasn’t clear, but the website had more info. Lawn weed products are designed for grasses only and aren’t always safe around ornamental plants, so be careful if you’ve got naturalized crocuses in your yard.

In general, I would use corn gluten meal (or just pull the weeds by hand), simply because I don’t want those other chemicals in my yard. Many chemical herbicides are known to be directly toxic to our health, not to mention deadly to the environment. I’d also focus on enriching the soil and strengthening the desirable plants, because unhealthy gardens are prime targets for pesky weeds.

Further Information

How to Control Silverfish in Your Home

Julie Day — Mon, 18 Jan 2010 23:13:45 +0000

Boxes, paper, insulation, and damp spaces are likely to attract silverfish.

My downstairs neighbors have been remodeling their condo, and my place has been overrun with silverfish. I’m desperate to get rid of them, but I don’t want to use toxic chemicals. Help! -Tina

Silverfish (Lespisma sacchrina) are nocturnal members of the insect order Thysanura that thrive in high humidity and warm temperatures. They can move very fast, making them hard to see, and live on a diet that includes starchy foods, paper, and fabric.

While they don’t bite, silverfish are a creepy nuisance that can be destructive to your belongings. The best way to get rid of silverfish is to attack them at the source; however, in your case it sounds like the source is going to be impossible to find! The good news is, you don’t have to reach for the highly toxic sprays; in fact, some of the less-toxic options are the most effective! Here are some things to try:

Boric Acid: This is the most popular product for silverfish control, and compared to other products, boric acid is quite low on the toxicity scale. In fact, it has historically been used as a cleaning product. You can purchase boric acid powder to sprinkle in areas where silverfish are active. You can also find boric acid in ready-to-use products such as baits, wafers, and traps. Roach Ridd and Dekko Silverfish Paks are examples of products made with boric acid.

Diatomaceous Earth: The tiny silicate shells of microscopic sea diatoms are lethal to many insects, penetrating their exoskeletons and dehydrating them. Sprinkle diatomaceous earth in crevices, but make sure pets and children cannot get close enough to breathe it.

Pyrethrin: This is a chemical pesticide, but because it’s made from the seeds of the pyrethrum plant, it’s biodegradable and considered less toxic than others. It’s the active ingredient in many flea and tick pet collars. While no pesticide is completely safe, this might be a more attractive option than a harsher chemical. You can find pyrethrin sprays and powders at most garden centers, and you would apply it only in crevices and areas where the silverfish are active.

Jar Traps: Make your own silverfish trap by covering the outside of a glass jar with masking tape (to help the critters crawl in), then put crackers or something starchy in the bottom of the jar as bait. The silverfish crawl in, but they can’t get out.

DIY silverfish control:

Sticky traps: Make a paste of flour, water, and boric acid. Coat index cards with the paste, allow it to dry, and use as sticky traps.
Baits: Sprinkle boric acid on and around a cracker, and place it as poison bait. Be sure to put it out of reach of children or pets! You can also do this with diatomaceous earth.
Crevice sprays: Make a 5% solution of boric acid in water. Use a spray bottle or turkey baster to inject the spray into cracks and crevices. You can also spray the powder directly. This puts the treatment where you need it and reduces your exposure to the chemical.

Be sure to target:

Boxes and file cabinets
Insulation
Baseboards
Behind appliances
Cabinet tops
Light fixtures and behind electrical outlets
Behind siding and within walls
Holes where water pipes enter walls

To make your home less inviting to silverfish:

Fix Damp Spots: Leaky pipes, water condensation, damp basements, and humidity provide an attractive environment for silverfish.
Eliminate Food Sources : Silverfish eat starches and sugars found in paper, glue, book bindings, insulation, and cardboard boxes, and they usually hang out pretty close to their food source. Use airtight plastic storage bins for paper, and get rid of anything that you find full of silverfish.
Vacuum Crevices: Silverfish hide and lay their eggs in cracks and crevices. Dispose of the vacuum cleaner bag in the trash outside so they can’t crawl out again.

Further Information

Silverfish (AgriLIFE Extension, Texas A&M)
How to Get Rid of Silverfish (howtogetridofstuff.com)
Boric Acid (Al’s Home Improvement Center)
Boric Acid, Borates, Borax (beyondpesticides.org)

How To Encourage Cactus To Bloom

Julie Day — Wed, 13 Jan 2010 17:00:42 +0000

How do I encourage my indoor cactus plant to bloom? It was blooming when I bought it, but it hasn’t bloomed since. -Beth

Desert cacti (the spiny kind) are a challenge to get to bloom indoors, simply because we can’t provide as much light as a sun-drenched desert. In addition to light, two other important factors for blooming are:

Age: Some plants take years to mature. The best way to check this is to buy one that’s already blooming, as you did.
Dormancy: Many desert cacti bloom in response to a cool, dry, dormant period. During the winter, you should reduce watering to only about once a month—just enough to keep the plant from shriveling up—and move your cactus to a cool spot, around 50° F, that has plenty of sunlight.

Also, keep in mind these tips for year-round cactus care:

Indoor cacti do best in a sunroom or south-facing windowsill. They’ll receive the most sunlight, and the air around windows is generally cooler in winter than the interior of a room.
During the growing season (spring and summer), your cactus needs maximum light and heat. Put your plant in direct sunlight, and turn it occasionally for even light exposure.
It will also need more water during the growing season. Allow the top 2” of soil to dry out before watering the plant thoroughly until it runs out the bottom (empty the drainage tray). Imagine a sudden desert rainstorm that soon dries in the sun, so never leave your plant in soggy soil.
Fertilize cacti only in the spring and early summer, using a cactus-specific fertilizer or a highly diluted fertilizer lower in nitrogen and higher in phosphorus and potassium. Overfeeding will not make your cactus bloom!
Repot your cactus using a potting mix designed for cacti and succulents. Don’t water your cactus for a week after repotting.

How to Keep Koi Fish in a Pond During Freezing Weather

Julie Day — Mon, 11 Jan 2010 23:09:21 +0000

During this latest cold snap, my koi fish pond has threatened to freeze over. What should I do? -Brett

Ice by itself is not dangerous to koi, as long as your pond is deep enough not to freeze completely (3-5 feet or more). The danger to fish comes with the reduced oxygen and increased toxic gases caused by the sealed over water surface.

While you could move your fish and plants to a temporary indoor tank for the winter, or install pond heaters that use a lot of energy, in many cases you can overwinter your fish outdoors with a little care. Keep in mind these tips:

Aeration: Have an aerator running in your pond at all times to keep the water stirred and promote the exchange of gases. An aerator is a lot more economical than a pond heater, and it will oxygenate the water while reducing ice build up.

Ventilation: If you’re aerating the water, all you need is a small hole or two for the bubbles to escape. You don’t need to remove the rest of the ice from the surface.

Balance: Koi (and many other fish) go into a sort of dormancy in the winter, using less oxygen and naturally settling to the bottom of the pond where the water is warmer. Your aerator should gently stir the water without upsetting this natural balance. Go for a steady stream of bubbles, not a rolling “boil” or strong current. If your pond is 4-5 feet or deeper, put the diffuser at the middle of the depth range (not the deepest part) so that the fish can retreat to less-disturbed deeper waters if needed.

Ice: Don’t break the ice in your pond by hitting it, since the force can cause shock waves that may hurt the fish. Keep an eye on your ventilation hole and remove any thin ice before it becomes thick and hard. If necessary, you can sit a full, hot teakettle on top of the ice until it melts a hole. Otherwise, let it snow! The snow, ice, and surrounding earth will help insulate your pond from the frigid air.

De-Icer: If your pond threatens to freeze completely, you may need to install a de-icer to keep at least part of the water above freezing. Your fish will need a few feet of liquid water in the pond throughout the winter.

Further Information

Overwintering Koi Under Thick Ice (pondtrademag.com)
Do I Really Need a Pond De-Icer? (thepondguy.com)
Over-wintering Your Pond and Water Garden (pondsolutions.com)

How to Protect Your Home During Extreme Cold Weather

How to Prevent Late Blight in Your Vegetable Garden

Julie Day — Wed, 23 Dec 2009 18:03:16 +0000

Since potatoes are long-lived they can harbor late blight spores.

This year my garden was exposed to the late blight epidemic, and I lost most of my tomatoes. As I plan next year’s garden, what do I need to do to prevent another outbreak? -Karen

Late blight (Phytophthora infestans) is like the “flu” of vegetable gardens – it’s airborne, waterborne, and fast spreading, and it can wipe out tomato and potato crops in just a couple of weeks. Late blight generally comes in new waves every year, usually from:

Infected transplants at garden centers.
Infected potatoes that survive the winter underground.
Cool, wet weather.

Unfortunately, even the most careful garden can be infected by spores blowing in from elsewhere, but following these tips can prevent bringing in (or harboring) the spores in your garden:

Transmission: Late blight can only survive in living plant tissue – it doesn’t live in the soil, and it doesn’t live on seeds, tools, stakes, or cages. Make sure to harvest all your potatoes to prevent harboring the disease underground over the winter.
Planting: Start your tomatoes from seed, to avoid buying infected transplants. If your potatoes were affected, start fresh this year with seed potatoes that are certified disease-free. Throw away any “volunteer” potato vines.

Fungicides: Treating with fungicides can be used as a preventative measure on healthy plants, but late blight is not treatable once it strikes.
Act Quickly: If you see signs of late blight, pull and throw away the affected plants immediately to prevent spreading of the disease. It won’t get better!
Composting: Some experts recommend against composting the plants, but others feel it’s OK if done correctly. The key is to make sure the material is completely dead. Infected plant material and spores will usually be killed in a hot compost pile (over 115° F). To make sure, you can solarize infected plants before composting. Potatoes are tougher, however, so you may want to cut them up and spread them on the ground where they’ll freeze, and plow them in next spring.
Prevention: Use smart gardening practices to prevent fungal diseases. Water without wetting foliage, allow for plenty of air circulation, and make sure your veggie garden gets morning sun. Even though late blight doesn’t live in soil, practice crop rotation to prevent other diseases.

Further Information

Late Blight of Potato and Tomato (Maryland Cooperative Extension)
Late Blight: Frequently Asked Questions (Cornell University)
Can I Compost Plants Killed By Late Blight? (Penn State Master Gardeners)