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Gardening Notes for June 2021

June 3, 2021 By Bruce Crawford

Summer has arrived! The days are wonderfully long, rain has proven to be ample to S date, and the temperatures promise to become more summer-like as the month progresses. June is filled with chores that linger from spring, as well as preparations necessary for the garden to continue to thrive well into late fall. As the temperatures rise, enjoy the coolness of the early morning and evenings for those tasks requiring the most exertion, with the heat of the day reserved for light duties. Try to water in the early morning as well, since evening watering tends to promote diseases and evaporation is most extreme during the mid-day hours. Also, don’t forget your hat and sunscreen. Finally, remember to sit down with your favorite cold beverage to write in your journal and to enjoy the fruits of your efforts!

Things to do:

Flowers

Aechmea Harveys Pride

Finish decorating containers and mixed borders with annuals and tropicals. The rather chilly weather of May has pushed back much of the planting of tender plants to this month. Do not be bashful about using larger and bolder plants such as Banana, Canna, Alocasia, Colocasia or even some of the larger Bromeliads such as Aechmea ‘Harvey’s Pride’ as pictured at right. The bolder foliage adds a wonderful textural impact as well as foliage color.
Fertilize annuals with a liquid feed once per week through June to give them a good start. If you used slow release fertilizer in your containers, use a 50% dilute solution of liquid feed. During hot periods, containers may need to be watered twice per day, especially if they are in the sun and the pots are smaller than 12”.
If you have deer, apply a deer spray weekly or after a heavy rain. It is best to rotate weekly between three different types of sprays for best effects.

cutting Iris stalks

Deadhead May blooming Iris to reduce the occurrence of the Iris borer as pictured at right. Cut the flower stalks as close to the rhizome as possible. Study the blooms of your Iris; if the blooms are few and the foliage is limp or overly dense, the plant either needs division or to be moved to a more sunny location. If it needs division, August is the best time.
Weed! All of the rain and cool weather from May has created abundant growth and the spring blooming weeds are about to go to seed. Remember, weed seeds last an average of 7 years! Also, do not be afraid or feel bad about removing seedlings of the more aggressive perennials. Brunnera macrophylla is a beautiful spring blooming plant, but can monopolize a garden!
Deadhead the Peonies as they finish blooming.
Lightly fertilize repeat blooming daylilies and Roses at the end of the month for a good August/September bloom.
Resist the urge to remove the yellowing foliage of Daffodils and other bulbs until it has totally turned brown. The foliage is producing the carbohydrates and storing them to ensure a good floral display for next year.
Plant native plants! Help feed out butterflies, moths, native bees and caterpillars. We need our insects to thrive so that we can too!

Shrubs and Trees

For small trees and shade trees, pinch off most of the water sprouts that you see growing from branches or stems – typically they appear at points where water sprouts or a branch was pruned off this past winter! Removing them as they start to grow discourages future dormant bud break.
Many low branched trees may need to have portions of the lowest branches removed, as the new growth from May and early June adds weight to the branch, causing it to droop ever lower. This is a chore that often needs to be done each year until the tree is at least 15-20 years of age and the stems are of significant size to support the added weight.
Selectively prune 2-3 stems of leggy multi-stemmed shrubs such as Fothergilla that may be growing in too much shade back to 6-8” tall too promote new growth from the base. Early June is also a great time to prune Azaleas and Rhododendrons as they finish blooming, since it will not impact next year’s bloom!

Turf

Cut turf weekly. During periods of drought, irrigate the turf for extended periods in the early morning, promoting deep root growth. As the summer heat begins, raise the cutting height to 3” to reduce the stress on the turf.

Vegetables

Harvest spinach, lettuce, radishes and arugula daily. As the days become hotter, the lettuce will become increasingly bitter and less tasty. These plants will also produce flowers or ‘bolt’, after which the foliage becomes extremely bitter, so it is important to harvest while the plants are smaller. Once the plants begin to bolt, remove them and plant summer squash, okra, cucumbers, pole beans, or other vegetables that will provide a yield in 65-70 days (September into October).
Early June is time to thin your beets to 3” apart should you wish to harvest baby beets or 5-6” should you wish them to grow larger. Either pull out or cut off the  Harvest spinach, lettuce, radishes and arugula daily. As the days become hotter, the lettuce will become increasingly bitter and less tasty. These plants will also produce flowers or ‘bolt’, after which the foliage becomes extremely bitter, so it is important to harvest while the plants are smaller. Once the plants begin to bolt, remove them and plant summer squash, okra, cucumbers, pole beans, or other vegetables that will provide a yield in 65-70 days (September into October).
Early June is time to thin your beets to 3” apart should you wish to harvest baby beets or 5-6” should you wish them to grow larger. Either pull out or cut off the baby foliage, should you not wish to disturb the soil. Don’t throw away the leaves either, since they are a great addition to salads!

tomato planrs

It is not too late to plant tomatoes. Planting in June often avoids the problems with early blight as well! If the plants are leggy, bury the stem up to the first true leaf, as the stem will produce roots and yield a sturdier plant. As the tomatoes grow, make certain that they are staked, lifting the fruit to come off the ground and reducing the chance of decay.
For tomatoes, it is ideal to pinch off the lower shoots up to the point of the first flower cluster (pictured at right). This will allow for a more manageable plant and a more sustainable crop of fruit.
Plant Eggplant, Peppers, Okra, Basil and other plants that prefer heat of summer early in the month.
Mulch vegetables with newsprint or cardboard covered with straw, reducing weeds and water loss. This is ideal for Heirloom tomatoes since they need consistent soil moisture in order to discourage splitting of the fruit. You can also mulch with lawn clippings provided that herbicides or insecticides were not applied to the turf.
Stop harvesting asparagus and rhubarb. They need to produce stalks and leaves of sufficient size in order to develop the energy reserves for next year’s harvest (the same reason that you do not remove bulb foliage until it has turned totally brown).
Compost! If you have yet to set up a composting bin, this is a good time to start. Not only can most weeds (without seeds) go into the bin, but so can bolted lettuce plants and greens left from the dinner table. It is a great way to do our part to help reduce landfill waste.

Bruce Crawford
State Program Leader in Home and Public Horticulture, NJAES

June 2021 Plant of the Month – Mountain Mint

June 3, 2021 By Bruce Crawford

Mountain Mint – Truly, a Gardeners Mint

Mint is a plant that conjures up a multitude of thoughts and emotions among gardeners. Typically, our first thought is of a plant with wonderfully fragrant foliage that happens to combine well with Ice Tea and Mint Juleps! Unfortunately, this is matched with an equally unsettling vision of a plant that knows no boundaries and will rapidly spread throughout your garden! True mints are found within the genus Mentha, and their aggressively spreading nature makes them problematic in an ornamental garden. However, there are other plants in the mint family or Lamiaceae that display a far greater degree of garden refinement and manners. Mountain Mint, botanically known as Pycnanthemum muticum, is one such member of the Lamiaceae and it defies my imagination as to why this plant is not more popular among gardeners.

Mountain Mint is certainly not a new plant to the world of horticulture. It was first discovered by the French botanist Andre Michaux (1746-1802) in 1790, when he found masses of the plant growing in Pennsylvania! Michaux initially named and described the plant as Brachystemum muticum, which was published posthumously in 1803 in his work Flora Boreali-Americana. Interestingly, in the same book he described a new genus named Pycnanthemum! Both names are from the Greek to describe the flower structure; Brachys means short and Stelma means column while Pyknos means dense and Anthos means flower. It only took a few years for the French botanist and mycologist Christiaan Hendrik Persoon (1761-1836) to assign the proper genus name in 1806. The species epithet comes from the Latin Muticus for blunt, perhaps a reference to the dome-shaped or blunt appearance of the apical flowers. Although the common name is Mountain Mint, it actually does not grow in alpine regions, but rather in open, moist fields and forest edges, which can be located along the lower elevations of a mountain.

Personally, I was not introduced to this plant until 2010 while touring Central Park. It appeared periodically throughout the park as a 2-3’ tall mass of shimmering silver along the edge of woodlands and ponds. Although the day was cloudy and it was mostly growing beneath a canopy of tall trees, the plant gave the impression of sunlight cutting through openings in the branches and illuminating the forest floor beneath. The gentleman leading the tour mentioned how these masses of Mountain Mint had been installed in an effort to reduce weeds. Naturally, I thought it was another invasive mint and was about to dismiss the plant when he noted it was merely a dense, ‘weed-suppressing’ plant and not invasive. A weed suppressing, non-invasive mint – my interest in this plant began to grow!

The shimmering, silvery effect of the plant was not the result of a true flower petal, but rather a pair of silver colored bracts or modified leaves that subtend the terminal boss of small white to light pink flowers, as seen in the image above. Much like Poinsettias and our native Flowering Dogwood, the actual flowers are very small and the primary impact is created by these bracts. For Pycnanthemum, they provide a beautiful ornamental effect for over 3 months! The flowers themselves are roughly ⅛” long, white with pink markings and are densely arranged in a ½” diameter compressed flower structure called a cyme. It is this dense arrangement of flowers that sparked the crafting of the two initial genus names. The flowers open over a 3 month period beginning in June and are a great source of nectar for bees, beneficial wasps, moths and butterflies! In fact, it is rare that the plants are not a flurry of activity when in bloom. Come winter, the clusters of dried seed capsules atop the stems have a nice winter presence, especially with a heavy December frost as pictured at the end. My interest in this plant grew even further!

Mountain Mint The lance-shaped, dark green foliage, measures 2-2 ½ inches long and is much like a typical mint, the foliage is very aromatic when rubbed. Tightly clad to the square stems by only a short petiole, the foliage contains pulegone, an oil with an aroma reminiscent of spearmint that is very effective at repelling mosquitoes when rubbed on the skin. This aroma is also effective at eliminating deer browse!

Mountain Mint is a great plant for working into the Garden. It looks great paired with the silver foliage of Lamb’s Ear (Stachys lanata) and it is great at brightening the darker foliage of deep purple leaved plants like Purple Leaved Smoketree (such as Cotinus coggygria ‘Velvet Cloak’). I have found that the plants and stems have a very vertical appearance that can make a design look awkward when planted along the edge of a planting (as pictured at left) since the transition to the ground plane is very abrupt. It is best to have a lower growing plant or a mounding plant placed at the front of Mountain Mint to provide a more gentle transition to turf, a walkway or simply the ground plain. Plants grow well in full sun as well as light shade, providing that the soil does not become excessively dry for prolonged periods. The plants are adaptable to various soil types and pH; they are typically found growing on alkaline soils in the wild, but are tolerant of acidic soils and are surprisingly tolerant of moister soils along pond edges. The soils simply cannot remain waterlogged with ponding water for extended periods of time. The rhizomes do spread about 4-6” per year, but they are easily cut with a garden spade and the shallow stems are easily extracted, even if they have started to grow into a neighboring plant. This is a practice that should typically be done every other year.

Mountain Mint If more of a clump forming species is of interest consider Pycnanthemum flexuosum or Appalachian Mint. Originally named Origanum flexuosum in 1788 by the American botanist Thomas Walter (1740-1789), its name was altered a century later in 1888 by Nathaniel Lord Britton (1859-1934). Britton was the American botanist who went on to cofound the New York Botanical Garden! The species epithet means pliant and is probably a reference to the flexible stems. Growing 2-3’ tall and roughly as wide, the dense root system is great for soil stabilization and since the foliage is also aromatic, it too is resistant to deer browse. The flower clusters or cymes lack the silvery bracts of its cousin, but they are much larger, typically around 1 ½” in diameter (as pictured at right). The purple flecked, white flowers remain rather diminutive, with the ¼” long tubular flowers appearing for nearly 2 months throughout the summer. Like its cousin, they are also exceptionally attractive to pollinators. Unlike its cousin, each flower has a more pronounced calyx or leafy base that initially serves to protect the flower bud and then physically support the tubular flower. Once the flower fades and drops away, each of the 5 off-white sepals that compose the calyx have a long bristly spur at the tip, giving the flower head a Sputnik or fuzzy appearance. The ultimate effect produces a bit more drama to the flower and the Garden, which I found very ornamental! This species has similar cultural requirements as its cousin and both are hardy throughout NJ, easily enduring a zone 5 winter and the summer’s heat.

Interestingly, both species began their affiliation with horticulture under different and distantly related genera within the mint family, only to find out they were in fact closely related cousins. My interest and admiration for what these plants can provide for the Garden only continues to grow as I continue to find new ways to incorporate these plants in designs! Granted, no plant is perfect, since neither of these Mints should be eaten or used as a garnish in a glass of Ice Tea or a Mint Julep! However, if you have been searching for a deer resistant native plant that is friendly to pollinators, suppresses weeds and works well others, here are 2 mints that you surely want to add to your list of great garden worthy plants!
Mountain Mint

Bruce Crawford
State Program Leader in Home and Public Horticulture, NJAES

Gardening Notes for May 2021

May 3, 2021 By Bruce Crawford

Adequate April showers combined with seasonally appropriate temperature has provided early May with a very nice assortment of spring blooming plants. Although rather chilly for those looking forward to those summer days of 90 degrees, the cool weather will allow spring blooms to last and to be enjoyed to their fullest! May is always a hectic month, so take the time to make notes in your journal and take long evening strolls to smell and enjoy the fruits of your efforts.

Things to do:

Prune leggy Azaleas and Rhododendrons as they finish blooming. This will improve the habit or shape of the plant while still ensuring flower bud development for next year.
By late May it will be clearly evident which parts of a plant – if not the whole plant – has died back from winters chill and snowpack. Always check the base of the stems to see if mice have girdled any stems, often a problem when the snowpack has persisted for a long period of time.
If you have fertile soils, some perennials such as New York and New England Asters as well as the taller Sedums should be pinched in mid to late May to prevent them from flopping later in the season.
Some plants such as Bloodroot (Sanguinaria canadensis) can be easily sown in the garden by seed. Look under the foliage for the seed pods (pictured at right) and lightly squeeze the pod. If it splits open, the seeds are rip and spread them close to where you would like to add some plants. I say close since the seeds are moved about by ants, so the planting will take on a very naturalistic appearance, based upon where the ants finally drop the seeds! Other plants such as Winter Aconites (Eranthis) have seed that is dispersed out of the open, cup-shaped seed capsules by wind. As the plants rock back and forth, the seed is tossed a short distance from the capsules (as seen in the 2nd picture at right) and they will germinate the following spring. Longwood Gardens has found distributing the plant by seed to be a far more successful method of spreading the plants about than the typical method of installing the tubers in the fall.

Let bulb foliage turn yellow or tan before removing to ensure proper bulb and flower development for next year. Do not tie it together or braid it, since that reduces that amount of surface area exposed to the sun and its ability to make both sugars and next year’s embryonic flowers.
For bulbs such as Eranthis (Winter Aconite) and Galanthus (Snowdrops), dig and divide existing clumps as you will have far more successful results replanting the geophytes (plants with an underground storage organ, like a bulb or a corm) than planting newly purchased ‘bulbs’ in the fall!
If your Narcissus (Daffodils) failed to bloom this year, it may be they are planted too shallow for the bulb to grow to the proper size to bloom. Dig them in late May (as pictured at right), tease apart the clump into several smaller clumps and replant around 6” deep. In the clump pictured at right, notice the small bulb size of the one pulled down lower, far too small to yield a flower!

For a neat garden, edge those bedlines and compost the remnants!
Always make certain the soil has drained adequately before working it, as disturbing the soil while too wet will destroy the soil structure. If you can make the soil into a baseball, it is probably too moist!
For vegetable gardens, use a broadfork to gently loosen and aerate the soil. A broadfork has 3-5 sharp tines that penetrate into the soil with two 5’ long handles (as pictured at right). By using your body weight against the handles and rocking back and forth, the soil is loosened but not disrupted. Tilling the soil damages both the earthworms who help aerate the soil and beneficial fungus, which assist the vegetables in obtaining nutrients and water. Current research shows that the fungus also produce and transfer the amino acid Ergothioneine to vegetables. Ergothioneine is an antioxidant with anti-inflammatory properties that has been shown to battle chronic illness and allow people to live longer. You have to love fungus!  Get the soil for Vegetable Gardens tested for nutrients and pH level if it has not be tested in a couple of years.
If you are looking to ease into growing vegetables or you only have a deck, plant your cool season crops in containers. They are both ornamental and delicious (bottom picture on right)!
Thin those cool season vegetables like beets that were directly sown during April. Thinning will allow them to develop more fully and the greens from the thinned beets can be added to salads!

Start to plant frost tender vegetables. For the eager, the wall of water can be used for tomatoes and other tender vegetables that are planted during the potentially cold first half of the month, although there is no harm in waiting until early June! In fact, adding a second planting of tomatoes in early to mid-June will help to ensure tomato harvest through September.
Plant out tender annuals after the last frost-free date in your part of the state (generally May 15th, but frosts can occur later). Temperatures in May can fluctuate from 90° one day to 30° the next! Also, certain annuals that like it warm, such as Catharanthus (the annual Vinca) and ornamental Sweet Potato Vines should not be planted until late May or early June for best results.
Remove the Banana and Cana roots from the basement and plant them in a sunny location in soils that are enriched with compost to help hold moisture.
The Colocasia and Alocasia roots or potted plants can be planted out in early May. They are surprisingly tolerant of cooler temperatures when young.
Pot up the Dahlia tubers or plant them directly in the soil come late May.
Cut those lawns. Remember, 2 ½ – 3” length is far healthier for the turf than a 2” cut. Do not remove the clippings unless they are exceptionally thick, since they release nitrogen back into the soil as they break down.

Spot treat for dandelions or any other aggressive lawn weed.
Finish mulching perennial or shrub borders during the early part of May and start to weed! Remember the average weed seed’s life is 7 years, so remove those weeds before they go to seed.
Frequently visit local garden centers as new additions are coming in weekly.
Read the notes that you made this winter and last May and reflect on how to improve the garden. It is now time to put your thoughts into action!

Bruce Crawford
State Program Leader in Home and Public Horticulture (NJAES)

May 2021 Plant of the Month – Asimina

May 2, 2021 By Bruce Crawford

One of the positive developments from the pandemic is the renewed interest in gardening and in particular, growing food. I have always been astonished at how many children do not know how their food is produced, other than it magically appears on grocery store shelves. Obviously, their parents did not share a passion for growing food and hopefully, that will continue to improve once the pandemic is behind us. Some fruits are not only tasty and nutritious, but have an attractive ornamental appeal. For years I have been touting the beauty and benefits of Pawpaw Trees, botanically called Asimina triloba. Perhaps now, this tree’s time has finally arrived!

Pawpaw is a member of the Annonaceae or Custard Apple Family, containing upwards of 108 different genera and 2,400 species that are principally located in tropical and subtropical regions of the world. Asimina triloba is one of 12 species, all native to North America and is the most Northern and cold hardy species of the family, distributed from Georgia north to Ontario and west to Arkansas and Missouri. It typically appears in moist, well-drained areas along shaded streams, forested lowlands and wooded slopes. Pawpaw was initially named Annona triloba in 1753 by the Swedish Botanist Carl Linnaeus (1707-1778). The genus is still in existence with around 166 species and was derived from the Taíno word Anón for fruit. Taíno was the name of the culture of indigenous people in the Caribbean prior to the arrival of the Spanish. The genus name of Asimina was penned by the French Botanist and Naturalist Michel Adamson (1727-1806) in 1763. The word was adopted from Assimin or Rassimin, as the tree was so named by the Native American Algonquian Indians. It was not until 1817 that the French Botanist Michel Felix Dunal (1780-1856) properly described the tree as Asimina triloba, although the tree continued to undergo various renditions until 1886 when it was conclusively decided by the American Botanist, Asa Gray (1810-1888) that Dunal was correct. The species epithet means 3 lobes and describes the double whorl of 3 petals that comprise the flower (see images below). The common name of Pawpaw is believed to have come from the Spanish Papaya due to the similarity of the fruit shape, size and taste.

Although Pawpaw is hardy to zone 5, its appearance certainly reflects the tropical and subtropical regions inhabited by the remainder of the Custard Apple Family. The oblong foliage is 6-12” long with a pronounced outward and gently drooping display. The leaves are arranged alternately along the stems and come autumn, develop an attractive yellow fall color in shade (picture above), although it can blend with orange when grown in full sun (pictured at left). Asimina is an understory tree, typically growing to 15-20’ in height, although heights of 30’ are not uncommon when conditions are ideal. Although it grows in shaded locations in the wild, it adapts very well to full sun in the home garden, provided it is given a little protection from the afternoon sun for the first year or so. The 1-2” diameter flowers are bell-shaped or campanulate, with the dangling flowers beginning to open along the leafless stems in mid-April. The flower buds open sequentially from the inner reaches outward, which is a great adaption in case of an unexpected late spring frost; the closed flower buds are not impacted by the chill and subsequently continue to open and ultimately bear fruit! The flowers are initially a pale green on opening as pictured above, but gradually change to a deep ‘meaty’ red at maturity. The flowers consist of an outer whorl of 3 lightly pubescent sepals or modified leaves that are also initially green before developing dark red highlights with age. The sepals and flower stem are lightly pubescent and are located at the top of the flowers once open as seen above. The six petals are arranged in two distinct tiers of three, with a larger outer whorl and a puckered inner whorl (as seen at left). The flowers have a slightly fetid odor, which in combination with the deep red color of the flower provides the clues for which creatures serve as pollinators – namely flies and beetles! Not to worry, I have never seen flies hovering around the trees and there is always good fruit set. It is important to plant several different clonal selections of Pawpaw, since the trees are not self-fertile and require at least two genetically different plants for pollination. The species exhibit what botanist call protogynous dichogamy, whereby the female stigma and the male anthers mature at different times, preventing self-pollination and inbreeding depression. My experience has been pruning the plants into a somewhat planar or two dimensional configuration, combined with removal of the root suckers helps to enhance flowering and fruiting.

Pawpaws produce the largest edible fruit in North America (pictured below), ultimately reaching lengths of 3-6” and weights upwards of 5-16 oz.! When ripe, the fruit changes from green to varying shades of light yellow, with a sweetly aromatic fragrance and a slight softness to the touch. The fruit’s taste also has tropical overtones with accents of mango and pineapple, yet with the texture of ripe banana or custard. The ripe flesh is best eaten with a spoon or made into ice cream, a smoothie or used in baking. Using a spoon is also handy since the fruits have two rows of large dark brown seeds that are challenging to eat around! The fruit has to be picked when ripe since, at least in my experience, they fail to ripen if picked too early. They also have a very short shelf life of only a few days, although the pulp can be frozen for up to a year if properly processed. Aside from sweet tasting, the fruit is also very nutritious, containing healthy amounts of Vitamin C, Magnesium, Iron, Copper and Manganese. They are also a good source of Potassium and antioxidants.

Of course, the plant did not develop these delicious fruits in conjunction with the evolution of Homo sapiens, since fossil records of Asimina date back 23 to 54 million years ago, long before the appearance of our ancestors. It is known that fruit eating Megafauna or mammals over 100 lbs. such as Mastodons, once roamed North America and were responsible for not only consuming the fruit, no doubt in one ill-mannered bite, but spreading the seed and slowly enlarging its native territory. With the loss of many of these animals between 12,000 and 13,000 years ago, the reproduction and distribution of many plants was also impacted. One rather annoying characteristic of Pawpaw is its strong tendency to sucker from the rootstock and create colonies. Although bothersome in the Garden, this trait may have allowed the plant to endure; since there was no longer a vector for seed distribution, the production of new stems allowed a colony to endure as the older trunks failed! As the Native American Indians slowly spread throughout North America, they in turn took over the task of the megafauna in spreading and planting the seed! Another trait that is both beneficial and problematic is the lack of insects or animals that eat the foliage or stems. Rarely is deer browse evident. Initially, this may sound beneficial, but like many members of the Annonaceae Family, Asimina contains acetogenins that function as a neurotoxin. These compounds are most concentrated in leaves, young stems and unripened fruit, which explains the lack of deer browse. It is also present in ripened fruits. Many cultures throughout the tropics create a tea from the leaves of plants from the Annonaceae family, which supposedly acts as a sedative. Over the course of a lifetime, this consumption creates an atypical form of Parkinson’s disease. The point being that one should not overindulge in the fruits either, but rather practice moderation!

Pawpaw is a plant that is entrenched in American culture. According to the writings of Lewis and Clark in September of 1806, Pawpaw fruits sustained their expedition for several days after their supplies dwindled and both George Washington and Thomas Jefferson were great fans and grew trees in their garden. It is certainly not without its faults. However, it is a great plant for people who are exploring fruit and vegetable gardening for the first time or well-seasoned gardeners who are interesting in exploring new food options. Without doubt, it is a delicious and ornamental tree for your garden!

Bruce Crawford
State Program Leader in Home and Public Horticulture (NJAES)

Gardening Notes for April 2021

April 2, 2021 By Bruce Crawford

As we experienced a year ago, the act of getting out into your Garden continues to be a great option as many of us continue to work at home. Plants continue to display their beauty and working in the soil and seeing things grow is a very calming. This will probably be a year that many homeowners continue to grow their own vegetables, and the garden retains its importance to many home gardeners. As the sun and warmth of April unfold, take a deep breath and prioritize what must be completed vs. what could be postponed for a day or two. Remember, gardening is our hobby and we do not need any more pressures or deadlines in our life!

Things to do:

Finish pruning roses, small trees, and coppiced shrubs early in the month. Techniques for pruning red and golden-stemmed dogwoods (Cornus sanguinea cultivars) and willows (Salix), depends upon the deer browse pressure. Either ⅓ to ½ of the older stems can be cut back to 6-12” or the entire plant can be cut to that height as seen in the image below of a Red Stemmed Willow (the pruned plant is at the right of the image). Leaving some of the existing stems helps protect the young shoots from deer predation. Shrub roses can be cut in half to prevent them from becoming overgrown, while the stems of hybrid tea roses should be cut down about 2/3’s to a bud that is facing outward. Hydrangea arborescens cultivars can be cut back to 3”; Hydrangea paniculata cultivars can either be cut back severely to 12” or pruned lightly, leaving a 3-4’ tall framework for new growth to emerge; Hydrangea macrophylla should be thinned with the oldest and most branched stems cut to the ground while Hydrangea quercifolia should simply be lightly shaped.
For ornamental flowering trees, thin out any water sprouts or ‘suckers’ that appear on branches that will grow into and become abrasive to existing branches above. Branches that rub against each other damage the bark and allow air and decay to impact the branches.
Finish cutting back ornamental grasses and perennials.
If you overwintered bananas outside (such as Musa basjoo), remove the insulating leaves and the surrounding wire cage.
Divide grasses and perennials if necessary. Remember that the center portion of the plant is the oldest and least vigorous and should be discarded. The outer, more vigorous ring will yield at least 10 new plants, with 9 of those going to friends, a new garden, or a curbside sale!

As soon as the early blooming bulbs (such as Snowdrops, Winter Aconites, Snowflakes and Scilla) have finished blooming, the clumps can be dug, divided and moved about the garden if so wished. These bulbs are much more successfully spread about in spring while still actively growing than when purchased as dormant bulbs in autumn. It is also financially more prudent!
If your Narcissus have stopped blooming, they may be planted too shallow or are in need of division. Plants can be dug, divided and replanted while in leaf, as seen at left.
Continue potting up Canna, Banana, Alocasia and other tropical plants that were overwintered in the basement. Make certain to test the tubers to ensure they have no soft spots or decay
Edge bedlines and compost the pieces of turf that have been removed.
Finish thatching and raking lawns. Apply a pre-emergent crabgrass control to established lawns before or during Forsythia bloom, if crabgrass was a severe problem in 2020.
Apply fertilizer and lime to lawns and Vegetable Gardens as prescribed by soil test results.
Apply corn meal gluten to flower beds as a weed pre-emergent and mild fertilizer as an organic alternative.

For the Vegetable Garden, finish sowing tomato, pepper, and eggplant seeds. Earlier seeded Lettuce, Swiss chard, broccoli and cabbage seedlings can now be planted outside, especially under low tunnels or in containers. Many new gardeners do not realize how many vegetables can be grown on a sunny deck in a container! For tomatoes, if you sowed your seed in a tray and the first leaves or Cotyledons are now well developed, tease apart the seedlings and install the plants in individual cells. Tomato seedlings can be planted deep, since roots will develop along the entire stem, providing a stout and strong plant (see images above –planted too shallow on the left, planted to the proper depth on the right).
Resist the urge to turn over or work the soil of your vegetable garden if the soil is too moist. In fact, try not to even walk on the soil if possible. If you can make baseballs from the soil, it needs a few more days to drain.
It is best to actually put a soil fork into the ground and rock it back and forth to loosen the soil, vs rototilling. Breaking apart the soil damages soil borne mycorrhizae, which in turn enhance the growth of your vegetables!
Early in April for those in Southern locations, later for those more Northern areas, seed can be sown directly in the garden for Beets, Carrots, Spinach, Cilantro, Lettuce, Arugula, Mustard Greens, Bok Choy, Peas and Turnips.
It is time to plant potatoes, as they are typically planted 2-3 weeks prior to the frost free date (May 15 in central NJ). Only use ‘seed’ potatoes from a seed company and resist using potatoes that you have bought at a grocery store that are sprouting!
Remove the wintergreens from containers and plant bulbs, pansies, primroses, evergreen grasses, etc for early spring color. Consider using the grassy foliage of Acorus gramineus ‘Ogon’, the Golden Sweet Flag pictured below, as a chartreuse accent plant for spring containers! Also consider many varieties of Lettuce and Swiss Chard, as they are also very attractive and mix well with Pansies and Primroses. Plus, you can harvest a meal right from your containers!