Late winter to early spring is a terrific time for pruning many shrubs. What should you prune and when? You could study pruning for an entire semester, but here are some basic guidelines. I recommend that you properly identify, then research, each particular kind of woody plant before you consider your first cut:
- Safety first 1) If any part of a tree or shrub is within ten feet of any kind of electric cable or wire, stop and call a professional. 2) Wear gloves and sturdy shoes, and use only sharp tools like bypass (not anvil) hand pruners and loppers, and saws. 3) Sanitize your tools and gloves with isopropyl alcohol or a product like Lysol spray before you start, and again when you’re done pruning each individual plant.
- General concepts Notice the overall shape of the shrub. Most flowering shrubs should be balanced and open in their center. Start pruning by removing all dead and diseased branches, then look for branches that cross or touch each other. Rubbing branches damage the bark tissue, inviting pathogens and pests, so remove one or both branches, depending on their condition, all the way to the base. Branches that grow from the perimeter towards the center should usually be removed. To shorten a branch or twig, cut it 1/4 inch above an outward-facing bud so new growth heads towards the perimeter of the shrub.
- When does your shrub bloom? 1) For spring bloomers, pruning them during the late dormant period (late winter/early spring) will remove flower buds, which were formed last year after the shrub bloomed. No flower buds, no flowers, so wait until after they bloom this year. 2) For later bloomers, pruning them now, before they form this year’s flower buds, is ideal. These can also be pruned soon after blooming.
- Roses Relax. Roses are simply shrubs that benefit from annual pruning. Prune in late winter to early spring (late dormancy) or when the buds start to swell. First cut out dead, broken, diseased and crossing canes. Put all your pruning debris in a trash bag and throw it away. Do not compost. Fertilize your roses with something like Espoma Rose-Tone or a good organic slow release fertilizer by following the directions on the bag. Climbers like to keep their main stems, so keep them fresh by pruning their lateral branches. Once the main stems are three years old, consider cutting one or two of them to their base to encourage new ones. Then cut one or two of the oldest every year. For shrub roses, cut up to 1/3 of the canes, the oldest, thickest woody ones, to their base as you open up the overall look to a vase shape. Cut to their base any super skinny canes from last year. For height, cut the remaining canes to about 1/2 their height, 1/4 inch above a robust outward-facing bud.
Please feel free to contact Carol with any questions.
Here’s the short answer to how to stake peonies, Rudbeckia laciniata ‘Herbstonne,’ baptisia, asters and other tall and/or vase-shaped perennials that are at risk of collapsing under their own weight this season. Do these in the spring:
EIGHT STEPS TO STAKE GARDEN PEONIES
- Get stakes, twine and pruners.
- Set five stakes evenly around peony.
- Tie twine to one stake.
- Loop twine around each consecutive stake.
- Return to and loop around first stake.
- Loop twine around every other stake.
- Return to first stake
- Cut and tie off twine.
For more answers, here’s an expanded explanation:
- Gather five garden stakes for each perennial, plus twine and sharp scissors or pruners to cut the twine. Safety glasses or goggles are a great idea too, as getting your eye poked by a stake takes all the fun out of staking.
- Push your five stakes into the ground, evenly spaced around the drip line of your perennial. If you view your perennial from above, the drip line is the circle or perimeter of the foliage from which water drips to the ground.
- This third step completely encloses all your perennial stems. Starting with a stake that is towards the back of the perennial, tie a slip knot around the stake about 15 inches above the ground. Next, one stake at a time, consecutively, draw your twine around your circle of stakes, making a complete loop (not a knot) around each stake as you go. When you get back to your starting stake, make a complete loop around it, too.
- This fourth step creates a supporting matrix of spaces through which your stems will grow. Resuming at what was once your first and is now your last stake, draw your twine around every other stake, making a complete loop around each of these stakes as you go. You may need to carefully pass the twine between stems to reach your next stake. When you get back to your original stake, cut your twine long enough to tie a slip knot, and tie the knot. If you’ve done this correctly and you could look at it from above, your twine pattern will look like a star inside a circle.
- Repeat steps 3 and 4 at least one more time, higher up on the stakes to support future growth. You may be tempted to cut the stakes to a lower height, but you’ll risk not having enough support for the flower stems once they elongate and your flowers are in full bloom, especially after they become heavy with rain.
Please join me at 7 p.m. tonight at the Easton Garden Club’s monthly meeting where I’ll be leading a free soil testing workshop and also presenting a brief tick talk. The meeting is at the Covenant Congregational Church on Centre Street, in the basement gymnasium. More comprehensive testing from UMass for fertility or fertility plus organic matter is available at a small extra cost. The Club will provide bags and ship your sample to UMass.
For each garden area you want tested, bring one clean one-quart clear glass jar and lid, with 3-1/2 cups of dry soil.
THE SINGLE MOST IMPORTANT THING ABOUT SOIL TESTING is to properly sample and let your soil air dry. Info and instructions are below.
What to Bring:
1 Clean, dry one-quart clear glass jar with fairly straight sides, with a tight fitting lid for each sample you want tested. A pasta sauce or mason jar works quite well.
3-1/2 Cups of dry soil in your jar for every sample you want tested. **REMEMBER to properly sample and dry your soil before putting it in your jar.
How to Sample Your Soil:
The most critical step in soil testing is collecting the sample. It is important that you take the necessary steps to obtain a representative sample; a poor sample could result in erroneous recommendations.
The first step is to determine the area that will be represented by the sample. For instance, your veggie garden might be one sampling area, your front island bed another, and your backyard lawn still another. Soil physical appearance, texture, color, slope, drainage, past management and current intended use should be similar throughout the area. It may be helpful to draw a map of the property and identify areas where you will collect samples.
Using a clean bucket and a spade, auger, or sampling tube collect 12 or more sub-samples to a depth of six to eight inches (four to six inches for turf) from random spots within the defined area. Avoid sampling field or plot edges and other non-representative areas.
Avoid sampling when the soil is very wet or within six to eight weeks after a lime or fertilizer application. Next, break up any lumps or clods of soil, remove stones, roots, and debris, and thoroughly mix sub-samples in the bucket. Once the sample is thoroughly mixed, scoop out a little more than one cup of soil and spread it on a clean sheet of paper to air-dry. A fan set on low will help speed the drying; do not apply heat.
#1. CAUTION: WET SOIL – DO NOT ENTER YOUR GARDEN – OR WORK ON YOUR LAWN!
- Our recent rains have left our soils saturated, and if you step into your shrub and garden beds now you’ll be causing mostly invisible but meaningful damage that makes it harder for your plants to thrive.
- Compacting your soil: plant roots depend on the spaces between soil particles to hold water and oxygen. When you step on wet soil, you compact these spaces and your plants suffer.
- One cup of soil may hold as many bacteria as there are people on Earth, never mind the fungi, protozoa, nematodes, arthropods, and earthworms – most of which are beneficial to you most of the time. Together, these tiny beings are a living system called the Soil Food Web, and it’s best to not to step on them when the soil is wet.
- To test if your soil is dry enough, take a handful of soil and squeeze it. If the soil crumbles easily when you open your hand, it is ready to be walked on or tilled. If it does not crumble, it is too wet. Allow the soil to dry for a few more days and test again before digging.
#2. GET YOUR SOIL TESTED – BEFORE YOU PLANT!
- Before planting is a good time to get a Routine Soil Analysis from the UMass Soil and Plant Nutrient Testing Lab to check pH and fertility. This economical soil test will provide recommendations for liming and fertilizing as needed, as well as indicating the lead level in the soil.
#3. START YOUR COOL-SEASON VEGETABLES – ONCE THE SOIL DRAINS!
- Now is a good time to sow seeds of cool season crops such as peas, lettuce, chard, kale, arugula, spinach, carrot, radish, beet and turnips.
- Plant the seeds as soon as the ground can be worked. Sow your spinach, beets, radish, carrots and lettuce thickly in rows and thin later to the desired spacing (read the label) and to allow them to develop properly. Root crops such as carrots, beets, and radishes should be thinned to a 2-inch spacing to allow the roots to develop properly. They can be thinned as soon as they reach small edible size.
#4. EAGER TO JUMP START YOUR LAWN?
- Your doctor wouldn’t give you a treatment without first making a diagnosis, right? Same goes with your lawn. Why treat your lawn for grubs or other turf insects if you don’t first discover what’s causing a problem? Grub populations are easy to evaluate, as are other sub-surface and surface insects. Once you diagnose properly, you can treat with a reasonable solution rather than automatically throwing money and chemicals at the situation.
- Start weaning your lawn off the expensive, stepped conventional petrochemical-based fertilizers by switching to a slow release, low-nitrogen organic fertilizer like Roots Fresh Start. Apply once in early spring after the soil has begun to warm up and apply again in early fall. The water-insoluble nutrients will be recycled and released by your friendly soil microbes slowly over the entire growing season as they’re needed by your turf, rather than getting flushed (along with your money) away with rain and any irrigation.
- Doing a lawn renovation this year? Wait until September for best results and return on your investment.
#5. MONITOR FOR WINTER MOTH CATERPILLARS
- Winter moth caterpillars cause damage to many different deciduous plants such as oaks, maples, cherries, ash, crabapples, apples and blueberries. their eggs typically hatch early-mid April, and the young larvae quickly start feeding on flower buds, leaf buds and young developing leaves.
- Winter moth egg hatch has not yet been observed for this growing season as of 4/5/17 in Massachusetts. Scouts are still reporting that winter moth eggs are orange in color and have not yet turned the blue color that indicates hatch is imminent. Eggs can be sprayed with dormant oil before they hatch, but the eggs can hide under pieces of bark and be hard to reach with spray.
- Once the caterpillars hatch, they’re eager to eat their host plants. Dormant oil will no longer work, but there’s a fairly safe treatment that simply takes their appetite away. It’s a kind of bacteria called bacillus thuringiensis var. Kurstaki. In some forms it’s approved for use on organic farms. Always read and follow the label.
(BONUS #6.) CELEBRATE ARBOR DAY BY PLANTING A TREE ON APRIL 28
- Arbor Day is an annual observance that celebrates the role of trees in our lives and promotes tree planting and care. The best tree selection may be a native tree that is well suited to thrive in your yard with your existing soil, sun, water, and other cultural conditions. Have your soil tested before investing in your new tree or shrub.
AS ALWAYS,PLEASE FEEL FREE TO CONTACT ME IF YOU HAVE ANY QUESTIONS OR NEED A HAND!
EMAIL CAROL OR CALL 617-327-9254
Could it be rhododendron borers? I started spring pruning for an organic gardening client in Sharon last week, on one of those yummy sunny 60 degree March days. Near her front door are broadleaf evergreen shrub beds on either side of an elegant entry path. My goals were to prune out any dead, use selective pruning to open up dense areas and stimulate new growth for a more balanced and pleasing form of individual shrubs and their big picture impact, and scout for pests.
A dead branch on a rhododendron caught my eye. I’m always very curious about why plants and their parts fail to thrive, so I investigated a bit. I cut off a portion of the dead branch and in its cross section found a dead giveaway of a clue.
It looked like an electric drill had made a 3/16 to 1/4 inch diameter hole in the interior of the stem, parallel to the length of the stem, and I knew right away it was quite likely the work of a rhododendron borer. I kept cutting the branch closer and closer to the ground, and found that the borer hole went all the way down to where the stem met the root flare at soil level. It may be that a second year borer spent some time in the roots, then bored its way toward the tip of this branch, contributing to its demise. I’ll continue to watch carefully for signs of activity and damage, and remember that borers are just one of several flavors of rhododendron pests.
How do you treat something like borers? Try the following methods, or contact me when you see damage and you need help gathering evidence and deciding how or whether to save your valued shrubs and trees.
Treatment for Rhododendron borers:
- Look around for dead branches and cut a cross section of one. Look for other signs such as a borer’s exit hole through the branch, frass (insect poop that resembles sawdust), and the condition of the leaves and stems. Photography these signs for your records.
- Be sure to properly identify the pest that is doing the damage. FYI there’s a separate and distinct Rhododendron stem borer
- Cut out and destroy all affected tissue – or save a sample to send to a lab.
- Whether there’s an effective pesticide for the two types of Rhododendron borers seems to depend on what extension service or licensed pesticide professional you ask, and in any case monitoring and prevention are the best next steps. This is an organic client who prefers organic treatments for the health of her family and the environment. An injection of nematodes into the stems may be appropriate if she has the stem borer. I’m looking into it.
Tips to help reduce borers:
- Keep mulch at least 2-3 inches away from the base of of all plants where the stems meet the earth, including rhododendrons. Your mulch should never be more that 3 inches deep.
- Keep shrubs well watered during dry periods. One inch of water per week is generally sufficient for established, healthy plants. More water than this is usually needed for plant establishment.
- Avoid wounding shrubs, as wounds can make it easier for insects and pathogens to enter. If your plants have any branches that directly cross one other, they probably rub against each other when it’s windy, causing abrasion damage and creating entry points for pests and pathogens. Also, do not wound shrubs with lawn mowers and string trimmers.
- If you don’t have an edged bed around a tree or shrub, make one large enough so that not only will your string trimmer no longer nick the trunk, but the mower won’t run over the root zone. A general guide is to edge out a bed that goes all the way to the drip line, defined as the area all the way from the trunk to the outermost circumference of the tree’s canopy . After cutting out and removing any lawn or weeds, etc. from your edged area, apply 2-3 inches of mulch to the bare soil.
Not all damage to rhododendrons is from borers. There are plenty more causes as well. So be careful, don’t jump to conclusions, get a positive ID, and get help if you’re not sure.
CONTACT ME IF YOU NEED A HAND
IF YOU’D LIKE ME TO HAVE A LOOK AT DAMAGED OR DISEASED PLANTS WITH YOU, I’LL PUT ON MY HORTICULTURIST HAT, HAVE A LOOK AND SUGGEST WHAT YOUR BEST NEXT STEPS MAY BE. CLICK HERE TO CONTACT ME