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Warm Weather in December
Martha Maletta, Home Horticultural Consultant
Dated -  December 18, 2006

Nearly the end of December. It has been hard to realize it because we’ve had some much mild weather. Cold will come but, hopefully, not too precipitously…for our sake and the sake of our landscapes.

Warm temperatures have probably delayed the normal acclimation (hardening) of trees and shrubs that enables them to survive the cold. If winter makes a sudden, dramatic appearance, cold temperatures that would not normally be a problem for hardy plants can cause freeze injury. Damage will show up as browning in evergreens and, as will be evident once spring arrives, in twig and branch dieback in deciduous species. Drought and freeze injury have also been implicated in plant susceptibility to certain diseases that cause dieback. We can’t do much about the acclimation problem; just hope that temperatures don’t drop too severely and suddenly.

Above average temperatures have kept lawns growing beyond the time mowers are usually stored for winter. I need to get one more mowing done so the grass isn’t too long when the season turns typical. Long grass can be susceptible to cool season disease and winter damage.

Hardy bulbs have apparently been fooled into thinking spring has arrived. Leaves are popping up and blooming crocus (the spring-flowering types) have been reported, but there’s nothing to be done. Once the ground freezes, the plants could be mulched to try to protect them, but some foliage damage is likely. Except for those blooming crocus, next year’s flower display is unlikely to be affected. That’s good news when I see the crocosmia in my garden looking more like it’s April than December.

I’ve seen forsythia, cherry, holly, viburnum and magnolia in bloom - at least a few blossoms here and there -over the last month. This premature flowering happens to certain plants when warm fall weather follows even a brief period of cold. Our temperate climate trees and shrubs have a chilling requirement to bloom, needing exposure to a certain accumulated number of hours around 40 degrees. Some species have a very short chilling requirement. These are the ones that will often put out a few blossoms in fall. The amount of flowering is usually not enough to noticeably reduce the springtime show.

Winter annual weeds look like they are off to a great start. These are the species, such as annual chickweed and corn speedwell, that germinate and grow very well late in the season, overwinter, and flower and go to seed in spring. Those small bright green plants in gardens and lawns look innocent now. Cultivate and mulch gardens if conditions permit to reduce problems for next year.

Deer ticks are known to be active as long as temperatures are 40 F and above. I would expect there was a lot of recent tick activity based on the weather and on the more frequent than usual extractions needed on my cats. Any one spending time in tick territory during mild days of winter should be aware that deer ticks may be looking for a meal.

Warm wishes for the holidays in this warm December.

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Cyclamen and Hibiscus
Martha Maletta, Home Horticultural Consultant
Dated -  Week ending December 13, 2006

Poinsettias are great winter holiday plants, but don’t ignore the others.
Cyclamen and hibiscus are two of many “alternative” offerings this season. Choose carefully to suite the home environment and enjoy many weeks, even months, of bloom.

The exotic flowers and tropical appearance may account for the cyclamen’s popularity as a winter flowering potted plant. The florist cyclamen (Cyclamen persicum) is one of 20 Cyclamen species that are native to the Mediterranean, southwest Asia and northern Africa. It was introduced to Europe in the early 1600’s.

Selection and breeding of the species, underway since the mid-1800’s, has resulted in the many cultivars now used in the floral industry with flower colors ranging from white through pink to shades of rose and red. Size varies, too. In its natural habitat, cyclamen grows during the cooler, moist seasons – fall, winter, spring. Plants go dormant when dry, hot summer sets in. So, cyclamen is best as a cool season houseplant. Plants are most likely to be available now through spring.

Provide cool temperatures, bright light and uniform moisture to keep a cyclamen vigorous and blooming. “Cool” means maximum 70 F during day (60-65 F better) with a drop to low 60’s or as low as 50 F at night. “Bright” means as much light as possible without direct south sun. An east window is a good choice. “Uniform moisture” means watering the plant frequently enough that the mix does not dry out but not so often that it stays soggy. Water thoroughly but never let the plant stand in water, and do not wet its center.

Over-watering, erratic watering and/or high temperatures probably account for most cyclamen failures in home settings. Lack of fertilizer will shorten the flowering period. Fertilize occasionally, starting about a month from purchase, using one-half the label-recommended rate. Given the right care, a cyclamen can keep blooming for at least several weeks. Then comes decision time: keep the plant and try to re-bloom it or discard it, let the professional growers do the work and buy a new plant next winter.

To re-bloom, the tuber needs a rest. Mimic summer and force dormancy by gradually reducing watering when flowering stops. The leaves will slowly (over two months) yellow and dry up. After carefully removing the dry leaves from the tuberous stem, there are various ways to proceed. One approach is to place the tuber in its pot in a cool dark place until mid to late summer when the tuber can be repotted (leaving it half exposed), watered and, when leaves appear (hopefully), grown as before with the addition of regular fertilization. The tuber must not dry out to the point of withering during storage.

An alternative is to repot the tuber right after the dry leaves are removed, begin watering immediately, and grow the plant outdoors in a bright, protected location until frost threatens. If successful, this method will promote earlier bloom. (New Jersey heat could be a problem, but our usual humidity might help compensate for it.) A third option is to remove the dormant tuber from the pot, clean it up and stored in dry peat moss or vermiculite in a plastic bag at 50 degrees. Then repot in late summer and grow as above.

Whichever method is tried, the plant must grow well and develop plenty of leaves to flower well. Bright light and proper night temperatures after buds form are also important along with a big dose of good luck.

Chinese hibiscus seems to be a popular houseplant and now, having grown a couple, I think I know why. The flowers are certainly spectacular... no question about that. But the special appeal may actually lie in the short life of those blooms. The overnight bursting of a bud (that has taken what seems to be forever to develop) into the magnificent flower that will be gone in a day or two captures my attention. A small hibiscus plant may produce only one flower at a time and not necessarily in rapid succession but even those single blooms are a treat.

In my experience, these plants seem to be adaptable to average home conditions, readily producing new growth and bloom as long as they receive plenty of light.  Many references recommend a south exposure and to keep bloom going during winter that may be essential. If a south exposure isn't available then a "winter rest" after the holidays- cool temperatures and with reduced water - might be a good idea.

These tropical shrubs can become large houseplants. For size control they can be cut back severely in late winter/early spring. Annual early spring pruning is recommended for hibiscus to promote vigorous new growth and bloom.

During the growing season (including all winter with plenty of light) hibiscus should be fertilized regularly with a water-soluble product with a balanced ratio of nutrients. I usually recommend using fertilizers at one-quarter to half the label rate and fertilizing somewhat more frequently than the label suggests, precisely how often being up to the grower's judgment.

The standard recommendation for watering hibiscus is to keep plants evenly moist (not wet, of course!). Mine don't seem to suffer unduly from drying somewhat between waterings. Temperatures should be in what is an average household range - 55 to 75 F. And although some sources recommend high humidity, others suggest average humidity and, again, my experience shows hibiscus to be adaptable.

The most common complaint I hear about hibiscus is bud drop, certainly a frustrating experience and particularly with this plant. Humidity and temperature, especially sudden changes in both or either, are generally the most common causes of this problem. So providing a "stable" environment is the best way to avoid it. 

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Geraniums
Martha Maletta, Home Horticultural Consultant
Dated -  Week ending November 03, 2006

They do make great houseplants and are cheerful addition to indoor winter decor. I discovered this myself having “adopted” two zonal geraniums (Geranium x hortum) that were living indoors without the conditions they needed: sun and cool night temperatures. Given a south window and winter night temperature in the low 60’s, they promptly flowered.

I’ve actually enjoyed my house-geraniums much more than geraniums in my gardens where New Jersey heat and humidity promote diseases that really take their toll. This is why it is probably best to buy geraniums specifically for growing indoors rather than to move them from garden to home. Pests and diseases often follow along when plants are brought in from the garden. Also, moved plants usually recover slowly…if at all…from the trauma of transitioning to pot from garden.

Geraniums need a potting mix and container that drains well because they will not tolerate a soggy root environment. Commercial soilless mixes or a homemade mix of peat moss and perlite and/or coarse sand are good choices. Don’t add a lot of gravel or potshards to the bottom of the container with the idea that it improves drainage. It doesn’t (see below). Simply fill the container with moist mix; there will not usually be a problem with it falling from the drainage holes. If there is, try using a piece of paper coffee filter or nylon screen to cover the hole.

Water geraniums regularly – they do not like desert conditions – but do not over-water. Feel the potting mix before watering, then water thoroughly until water runs from the container, but don’t let the pot stand in water for very long. Cool night temperatures, moderate day temperatures, ideally around 70 F, and a south facing window or other location that receives maximum sun, especially in winter, will produce the sturdiest growth and best flowering. The plants will survive lower light and/or higher temperatures but produce leggy growth and, most likely, no bloom.

Geraniums need some fertilization to keep growing and blooming, but don’t overdo it. I suggest using a soluble fertilizer and at one-half the rate on the product label until you see how the plant responds. Frequency will depend on how the plant is growing, a vigorously growing and blooming plant needing fertilizing more often than one that is slow-growing or resting.

The most common geraniums in the general market are zonal geraniums. They are available in many flower and leaf colors and patterns. but they might be hard to come by from plant sellers this time of year. Florists usually offer Regal (Martha Washington) geraniums (Geranium x domesticum) as pot plants. Being more difficult to grow outdoors in New Jersey than the zonals, using them as a houseplant is a chance to enjoy these particularly spectacular geraniums. They reportedly need very low night temperatures (40-50 F) to set flowers. Scented geraniums (several species) are grown for their fragrant foliage rather than their flowers that, though attractive, are not showy. These geraniums can tolerate lower light. Ivy geraniums (Geranium peltatum), with their trailing habit, are made for hanging baskets. They may need some sun protection in summer.

As for pot drainage, a layer of gravel or other so called “drainage” material, placed in the bottom of a pot, actually reduces the depth of planting mix that will be well drained. The bottom layer of mix in any pot will stay saturated for a while after a proper watering (water runs out the drain hole). The depth of this saturated layer will be the same – say one inch- no matter the depth of the container. In a six-inch deep pot filled with mix, only five inches would drain well. Add an inch of gravel and five inches of mix and only four inches of mix will be well drained and a suitable environment for good root growth.

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Leaf Color Change
Martha Maletta, Home Horticultural Consultant
Dated -  Week ending October 26, 2006

Why do leaves of deciduous plants turn color in the fall? (Hint: it’s not Jack Frost.) Leaves color (preceding leaf death) when days become shorter as the season changes from summer to fall and temperatures cool. Chemical and physiological changes in the tree and leaves result in the colors, dull or brilliant that we associate with this season,

Yellow that predominates in the fall color of many species is due to pigments called carotenoids, the same ones that make carrots orange. During spring and summer these pigments are masked by green chlorophyll. As the leaves begin to “shut down” in late summer and fall, chlorophyll breaks down and yellow color is revealed. (Essentially the same thing happens when a plant is not thriving: leaves may become yellow because something is interfering with the production of chlorophyll.)

Red and orange fall color is due to another group of pigments, anthocyanins. Tree species differ in their ability to form anthocyanins, so some will never turn red or orange while others, such as maple, are known for these brilliant hues. Fall breakdown of chlorophyll reveals these colors. Some species, notably oak, turn predominantly brown. Whatever fall color appears - brown, yellow, orange, red, purple, it is due to the various pigments, determined by species genetics, and chlorophyll residue in the leaf. Summer and fall weather conditions may influence the color display to some degree.

If your landscape could use some fall color, it is a good time to plant a deciduous tree known for that feature. Some species, however, are considered to be fall planting hazards and are best planted in spring. These include: birch, beech, ginkgo, magnolia, black gum, cherry and most oaks. Check with your nursery on best transplant season for particular species.

What ever the planting season, choose tree species carefully to suit the conditions of the site and the purpose in the landscape. And don’t forget to consider the impact of a tree’s root system on a given site, remembering that roots will ultimately extend well beyond the branch spread as the tree grows.

Trees cast shade and their roots compete for water and nutrients with other plants. Shallow-rooted trees such a Norway and red maple and those with fast growing roots such as poplar and willow make it difficult to grow other plants within range of their roots. Tree roots can cause problems with sidewalks, driveways, sewer lines and septic leach lines. For a tree’s sake and your sake, think “below ground” as well as “above ground” when choosing a tree for a particular spot.

The Rutgers Cooperative Fact Sheet “Transplanting Trees and Shrubs” is available on-line at www.rce.rutgers.edu or by calling the Rutgers Master Gardener Helpline at 908-788-1735.

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Mums
Martha Maletta, Home Horticultural Consultant
Dated -  October 06, 2006

Hardy chrysanthemums [Chrysanthemum (syn. Dendranthema) morifolium cvs.], natives of the Far East, are important for summer and fall garden color. Their diverse forms and hues provide plenty of variety. They are perennials but don’t always perform that way in New Jersey.

Flower form and size account for much of the diversity among these popular ornamentals. There are at least seven major flower forms. Singles are daisy-like flowers with one to five rows of long petals radiating from a flat center. Pompoms are small, stiff, almost globular flowers. Decorative types are those we most typically picture as a mum, and within this form there are many variations. Spoon flowers have, just as their name says, spoon-shaped petals. Spider flowered types have long tubular, hooked petals while those of quill flowered types are tubular but straight.

Florists and farm stands offer an abundant supply of potted mums this time of year, so it tends to be when we think of planting them. Actually, to try to establish a perennial planting of mums, spring transplanting is best. And cultivar is also very important in determining the longevity of the planting. But that doesn't mean we should pass up the offerings now available. Planted in a well-drained site and mulched for the winter, some fall plantings may survive for next year. And, of course, there's the enjoyment now.

To give fall planted mums a shot at survival, plant them as soon as they are available, and give them the care any new planting needs, especially regular watering. Choose a sunny spot with well-drained soil. Wet and heavy soil, especially in winter is deadly. When the ground is at least well-chilled, if not frozen, mulch the plants with 4 to 6 inches of straw or other mulch material except leaves, which tend to pack when wet. Some recent research indicates that winter survival improves when dead tops are not cut back until spring.

Several years ago, Rutgers did evaluations of garden chrysanthemum hardiness and growth the following year. (Plants were established as spring plantings.) Many did not survive or perform well the following year in spite of spring planting. Cultivar was clearly a factor. Probably the best way to obtain a reliably hardy mum is to take divisions in the spring from an established planting.

People sometimes wonder why the new mum that has survived the winter in their garden has grown much taller than it was as a fall purchased plant or has bloomed at a completely different time. Tall,” leggy" mums result when the plants are not pinched regularly, starting when new shoots are 5 to 6 inches tall and repeating with every 2 to 3 weeks until about mid-July. Leggy plants may also mean not enough sun; mums require at least six to seven hours a day. Mum cultivars bloom naturally at different times, from August through November. Commercial growers control growth and schedule flowering using temperature and light control and growth regulating treatments to bring the crop to market in late summer/early fall.

Mums make long-lasting cut flowers. To maximize their life follow a few simple practices Condition the flowers before arranging by stripping the lowest leaves, re-cutting the stems (under water if possible) and placing the container in a cool and dark place for several hours. Then arrange the conditioned flowers in a clean vase with warm water, removing any additional foliage that would be submerged. Use a floral preservative, if possible, purchasing a commercial product rather than trying to concoct one. The commercial products are specifically formulated to acidify the water, inhibit bacterial and fungal growth and provide nutrients to the flowers. Avoid using water softened by the ion exchange method that increases the sodium content and, if possible avoid fluoridated water.

Change the water or solution when it begins to look cloudy. Can’t see it? Change it after 2 or 3 days, but be sure to check the water level daily because fresh cut flowers can “drink” a lot, especially under warm or low humidity conditions. When some flowers begin to fade, remove them, and always re-cut stems when rearranging. Avoid arranging flowers with fruits and vegetables that may give off ethylene gas, shortening flower life.

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Composting
Martha Maletta, Home Horticultural Consultant
Dated -  October 06, 2006

Autumn leaves. The pleasures: wonderful color; woodland scent; the crunch and rustle under foot; and memories - of jumping piles and pleasantly smoky air.

The pain: dealing with the seemly endless annual deluge that buries the lawn and landscape. Some municipalities still collect leaves placed at roadside and deal with them through municipal composting facilities. And some leaves end up directly on agricultural land through on-farm leaf mulching that is regulated by NJ Department of Environmental Protection. On-farm leaf mulching involves spreading leaves and turning them directly into soil used for agriculture or horticulture.

The advantages of direct addition of leaves to soil are, ultimately, the same as adding compost: improvement in the moisture holding capacity, the tilth and the nutrient levels. Yet Rutgers does not recommend that home gardeners add leaves directly to their soil. It sound like an easy and good solution to leaf disposal, so why not?

The Rutgers Fact Sheet "Using Leaf Compost" explains that temporary nitrogen deficiency in plants may result from adding leaves directly to gardens. Where leaves are applied directly to agricultural land, careful planning and monitoring, in addition to modified fertilizing and cropping practices, are followed. These are not likely to be easily adapted to the typical home garden. Also, most home gardeners do not have the equipment for easily turning leaves into the soil.

So, it is best to compost leaves before adding them to the soil. Rutgers Fact Sheet "Backyard Leaf Composting" tells homeowners everything they need to know about this solution to leaf disposal. The section on "Constructing the Pile" spells out the “how to-s” and dispels some myths of composting. One is the “layer cake” approach. A proper compost pile can be constructed entirely of leaves. They do not need to be layered with grass clippings, manure, soil, fertilizer, lime or any other ingredient.

This is not to say that some of these materials may not be added. A small amount of grass clippings will not hurt. Other vegetable materials can be incorporated. A small amount of nitrogen fertilizer could speed the composting process, if desired. Limestone and soil are not needed nor are commercial “starters”.

Moisture and air definitely are needed for active composting. If materials being composted are dry, add water to the point where squeezing a handful produces a few drops. Adequate air should be present as long as the pile does not stay too wet and is not too large. Make sure the pile can drain after rain and do not use solid-sided bins. Maximum pile size is five feet high by 10 feet round or wide. (It can be as long as needed.)

To turn or not? The pile will decompose more quickly if it is turned regularly, especially during warm weather. But, if speed is no object, turning is not necessary. The very outer layer of an unturned pile may not compost at all, but the material inside will decay very well, though it may take up to two years.

Lots more details about composting are given in the Rutgers Fact Sheets “Backyard Leaf Composting”, “Using Leaf Compost” and “Home Composting” that are available at the RCRE website <https://njaes.rutgers.edu/extension/> under “Extension” and “Publications”. Copies can be requested from the Rutgers Master Gardener Helpline of Hunterdon County, 908-788-1339, M-Th 9-12 and M,W 12:30 to 3:30.

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Fall Lawn Care
Martha Maletta, Home Horticultural Consultant
Dated -  September 12, 2006

Fall is usually great for planting hardy ornamentals including bulbs and herbaceous perennials. Moderate soil temperatures and reliable rain help root development. Among hardy “bulbs” (some are not botanically bulbs) suggested as being deer-resistant - a very valuable characteristic for Hunterdon gardens - are: snowdrop, snowflake, scilla, grape hyacinth, crocus, chionodoxa (glory-of-the-snow), fritillaria, allium, eranthis (winter aconite) and daffodil.

Daffodil, narcissus, jonquil – different common names for a single group of plants that does seem to be practically deer proof, a rarity. They all belong to the genus Narcissus. There are more than 20,000 varieties and cultivars of Narcissus, making selection a puzzle as well as a pleasure. All this variety is grouped into 11 main divisions and 18 subdivisions. Popular terms distinguish them more simply.

The common name “daffodil” should refer to trumpet-flowered narcissus whose trumpet is equal in length or longer than what would commonly be called petals. The name “jonquil” should refer only to certain species - N. jonquilla, N. juncifolius – and their hybrids. It is correct to call any of these plants by the common name narcissus.

Several of the “deer resistant” bulbs bloom very early as their names suggest: snowdrops, snowflakes, winter aconite, and Siberian squill. They are generally small plants – less than 8 inches tall, so they are best planted in groups, spaced at 3-4 inches. Plant them where they will be seen in early spring but where they can be allowed to multiply for many years.

Grape hyacinth, fritlillaria and allium generally bloom after the early bulbs, even into June depending on species. And they vary in size from the small grape hyacinth to the four-foot tall crown imperial (Fritillaria imperialis). Allium species range from a few inches to a few feet in height.
All these bulbs need a well-drained site with some sun. Plant them where the dieing foliage in late spring and early summer will not be a visual nuisance or interfere with mowing or gardening. Soil should be prepared as for any planting, with additions of fertilizer, organic matter and, if soil pH is low, lime. Details, like planting depth, will vary with species and planting instructions should come with the bulbs.

Many herbaceous perennials can be planted or transplanted now, giving them enough time to settle in before winter. A general rule is to plant or move spring and summer bloomers now. Prepare the soil with lime, phosphorous and potassium, if needed. Move established and divided perennials with as much of the root system as possible. Pot-bound container-grown plants will need to have their root ball scored before planting. Plant at the same depth they were originally growing. Water plants in and keep them watered if rain is scarce. Mulch to conserve soil moisture. After the soil is chilled or frozen, mulch well to prevent freezing and thawing during winter that could heave new plantings from the ground.

Consult the Rutgers Bulletin E271 “Landscape Plants Rated for Deer Resistance” when choosing new perennials for the garden. It is available at the RCRE website <https://njaes.rutgers.edu/extension>. There is no guarantee when it comes to deer, but avoiding deer favorites is probably a judicious decision. Some popular perennials listed as “severely” or “occasionally severely” damaged are hardy geranium, hosta, bellflower, mountain bluet, chrysanthemum, daylily, rose mallow, phlox, and balloon flower. Fortunately, the list of those “rarely” and “seldom severely” damaged is quite extensive.

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Fall Lawn Care and Renovations
Martha Maletta, Home Horticultural Consultant
Dated -  September 12, 2006

If this is the year to tackle lawn renovation, the time is now. There are many advantages to seeding lawns in late summer/early fall. Lower air temperatures are perfect for the cool season turf grasses most of us grow, and soil temperatures are good for root growth. Rain is usually reliable, reducing need for irrigation.

If site conditions are suitable, consider seeding or renovating with turf-type tall fescue. Once established, these grasses are lower maintenance and more drought and pest tolerant than Kentucky bluegrass and fine fescue lawns. The appearance of new tall fescue varieties has been vastly improved over the old ‘Kentucky 31’ and varieties ‘Alta’, ‘Fawn’ and ‘Kenhy’. Texture is finer, color darker and growth lower.

Tall fescue‘s drought tolerance comes from the grass’s capability of developing a deep root system. Sites with shallow or poor quality soil may not benefit in this respect from use of tall fescue unless soil conditions can be improved. Tall fescue is shade tolerant but, like all other turf grasses, will not persist in deep shade. A vigorous tall fescue lawn can be successfully maintained with lower fertility than other cool season turfgrass lawns and with little or no irrigation.

Tall fescue is usually seeded without other grasses unless a small amount (5 to 15%) of KBG is added because it spreads by rhizomes more readily than tall fescue. Tall fescue does not blend well with perennial ryegrass or fine fescues because of differences in appearance and/or maintenance needs. If tall fescue is used for lawn renovation – seeding without tillage – it is best to eliminate existing grasses rather than seed into them. Tall fescue should be seeded by the end of September for best results.

For complete information on tall fescue varieties, lawn seeding, lawn renovation and many other lawn topics, visit the Rutgers Cooperative Extension website at <https://njaes.rutgers.edu/extension> or call or visit the Rutgers Master Gardener Helpline of Hunterdon County (908-788-1735, Building #2 of the Rt. 31 County Complex). Fall is prime time for many other lawn maintenance tasks: fertilizing, liming, dethatching and weed control.

Late September is an especially good time for treating broadleaf lawn weeds, if needed. Day temperatures are still warm and plants are actively growing. Fall application may be more effective on some very tough weeds like ground ivy than spring application. It is important to identify the weeds to be treated before selecting the treatment because species vary in their susceptibility to particular chemicals. Contact the Master Gardener Helpline for weed identification help. The RCE Fact Sheet FS385 “Broadleaf Weed Control in Cool Season Turfgrasses” has a very useful chart giving susceptibility of the most common turf weeds to the most widely used chemicals.

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Watering
Martha Maletta, Home Horticultural Consultant
Dated -  July 17, 2006

Watering is the most important care a homeowner can give new landscape plantings.
Trees and shrubs should be considered “new” for at least two years after planting and longer for larger transplants.

Water is the key to keeping new trees and shrubs alive and healthy until the root system expands, growing into the native soil. Moist soil is essential for good root growth. This means that the original root ball and the surrounding backfill soil must be kept moist but not wet to allow trees and shrubs to become established.

How much water is needed and how often depends on the type of root ball soil or container mix, the type and condition of the native soil, the size of plant and the weather conditions - plants will use more water on hot, sunny, windy days than on cool cloudy days. Trees and shrubs in Hunterdon County soil will generally need one to two inches of water a week (rain plus irrigation) to adequately moisten the root ball and the backfill soil.

Determining water needs more exactly takes a little doing. Keep in mind that one inch of water equals about 0.6 gallons applied to one square foot of soil area. Figure out how many square feet are included in the tree or shrub’s planting area and multiply by 1.2 to estimate the maximum gallons of water likely needed. Subtract recent rainfall (inches x 0.6 x square feet). (Don’t know how much rain? An inexpensive rain gauge is an essential gardening tool.) Measure the calculated amount of water in a bucket and apply. Or run a hose slowly into a bucket to determine how long it would take to apply that amount of water directly to the plant. Let the hose run slowly over the planting area for that amount of time, moving it frequently to wet all the root ball and backfill soil.

Check soil moisture an hour or so after watering. Dig a couple of narrow holes into the backfill soil to see that it has been moistened to at least 8 inches and that the root ball is moist, also. Water more, if needed. If the soil is very wet, reduce the amount next time because over-watering can kill plants, too.

Check the soil and root ball moisture again after one to two days. Root balls of container grown plants and B & B plants from sandy soils may dry out faster than the backfill soil. These plants may need to have their root balls watered more frequently than the backfill soil, possibly every couple of days. Check moisture of backfill soil after a few days. If a handful of soil falls apart after being squeezed, it is time to water even if the soil doesn’t feel completely dry to touch.

Adjust water amount and frequency based on experience, soil moisture and natural rainfall. Drought conditions will probably mean more frequent watering. Plants may not need to be watered as often once roots grow from the root ball into the backfill and surrounding soil.

Here are a few additional tips. Build a watering saucer if it was not created when the tree or shrub was planted, forming a low mound of soil around and just outside the edge of the planting hole to help hold water. Apply water slowly enough so it soaks into rather than runs off the soil. Use soaker hoses to apply water slowly, but check soil moisture carefully to learn how long to run the water. Keep soil mulched to reduce evaporation and weed competition.

A unique source for landscape plants is the Annual Rutgers Gardens Open House, Saturday, July 29th, 9 a.m. to 3 p.m. Besides plant sales, there will be guided garden tours, talks, “Ask the Expert” clinic, music, Jersey Fresh vendors, children’s activities and food sales. Admission is free. All sales’ proceeds directly benefit The Rutgers Gardens, which are located on Ryders Lane, just off Route 1 in New Brunswick. For more information call 732-932-8451 or visit <http://rutgersgardens.rutgers.edu>

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Garden Myths
Martha Maletta, Home Horticultural Consultant
Dated -  July 14, 2006

An article in a Virginia Cooperative Extension newsletter titled “Garden Myths” started me thinking about those and some other common gardening fictions. Here are some facts.

Gravel or similar materials placed in the bottom of planting pots or holes will NOT improve drainage. Instead, it reduces the depth of soil or mix that will be well drained after rain or watering. In pots, you might use a potshard or irregular pebble to keep mix from washing out of a large drain hole. Otherwise, just fill the pot with mix. Drainage problems in the garden can have various causes and remedies may be simple or complex, but digging a hole and putting gravel in it is not one of them.

Moss in a lawn does NOT necessarily mean that the soil is acidic. It does mean that conditions are not right for vigorous grass growth, so the moss has a chance to establish and spread. Moss does not kill grass. Low soil pH is only one reason a lawn may be more moss than grass. Other factors are: too much shade; poor drainage; low or incorrect fertility; soil compaction. To control moss, correct the condition or conditions that are keeping grass from growing.

Watering plants with a sprinkler on a sunny day will NOT burn the leaves. There are many other reasons to not water with sprinklers and avoid a sunny day, but burned leaves is not one of them. Water is lost to evaporation when sprinklers or other methods that throw water into the air are used. On a sunny and/or windy day the losses are increased. These methods also wet the foliage and can, if not timed correctly, increase disease problems. Where practical and possible, hand-held hoses, trickle irrigation or soaker hoses are best for watering the home garden.

Tomatoes should NOT be placed on a sunny windowsill to ripen. The sun’s heat reduces fruit quality and light actually interferes with the ripening process. Tomatoes should ripen until slightly soft to the touch in the dark at room temperature. For best eating, do not refrigerate and serve at room temperature. Prepare tomatoes just before serving because flavor decreases shortly after slicing.

Oak leaves do NOT make acidic compost. Finished compost from any source has a neutral or slightly alkaline pH. An oak leaf or pine needle surface mulch will NOT cause soil to become acidic. Mulches have little impact on soil acidity.

Needled-evergreens do NOT all need acidic soil. In fact, some – Douglas fir, Colorado blue spruce, arborvitae and yew, for example - require pH 6-7. The best chance to adjust pH for shrubs and trees is before or at planting, so a soil test should be a first step for any new addition to the landscape. It is much easier to raise than lower pH, so existing pH might determine plant choice. For example, soil with pH 7.0 would not be a good location for rhododendron.

All lawn weeds are NOT created equal in susceptibility to weed control chemicals, which are NOT created equal in effectiveness against all weeds. That is why it is important to identify weeds to be controlled before purchasing a product. Violets, ground ivy, corn speedwell, red sorrel and wood sorrel are among the most difficult lawn weeds to control while chickweed and dandelion are among the easiest.

One last very important fact. Organic, botanical and other “natural” pesticides are NOT harmless. In fact, certain common botanical insecticides are highly toxic materials. Products that are of low toxicity can have adverse environmental impacts if used excessively or inappropriately. It is the users responsibility to read and carefully follow the label on any pesticide, whatever its origin, to ensure safety for the user and the environment.

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Wood Mulch
Martha Maletta, Home Horticultural Consultant
Dated -  July 3, 2006

Wood mulch is a good thing as long as it is properly applied. No volcanoes around trees and shrubs, please! And keep it 18 inches away from house foundations and wood structures to avoid providing or concealing termite entry.

Wood mulch does not attract termites or harbor carpenter ants, contrary to some popular belief. Carpenter ants do not feed on wood. They excavate decayed wood such as fence posts, logs, stumps, and in building structure for nesting space. Wood chips are not suitable for that purpose. If carpenter ants are observed on wood mulch they are probably foraging for food, which includes dead insects.

Termites are a somewhat different story, but there is no direct termite hazard related to the use of wood mulch around the landscape. Research done at the University of Maryland found that organic mulch did not attract these wood-eating insects, and they did not consume it in any quantity. And it is highly unlikely that termites would be introduced to a site in a load of mulch since they do not live or breed in mulch. Subterranean termites are soil dwellers.

Mulch of any sort, including gravel, may enhance soil moisture (one of the reasons we use mulch) making it more suitable for termite tunneling. If mulch is spread so that it touches the house foundation, it could provide termites with a “bridge” over termiticide-treated soil. Mulch contacting siding or wood structure could hide evidence, such as mud tunnels, of a termite problem. These are the reasons for keeping the immediate foundation area clear of mulch and other debris.

What about the possibility of importing a plant disease with wood mulch? The consensus of some plant pathologists is that it is highly unlikely that pathogens would survive in chipped wood, and especially if it has been aged a few weeks or composted. As stated by one authority, “the immense benefits that mulching provides far outweigh the small concerns about spreading diseases.”

What about the Formosan termite-mulch scare circulated on the Internet early this year? Every authority I’ve read who weighed in on the issue essentially deemed it a hoax.

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