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How to Divide Bearded Irises

About every three years or so iris plants need to be divided, otherwise, they risk overcrowding and disease. The blooms will also suffer if they are not divided enough. The best time to divide bearded irises is from July through September, at least 6 weeks before the first frost.

Iris plants grow not from bulbs but from something called rhizomes. These form clumps with roots on the bottoms and leaves coming out the top. When these clumps get too big, they need to be divided and each new division will form a new plant.

So what do you do when it’s time to divide your bearded iris rhizomes? Using a garden fork, dig up your iris rhizomes and shake off the soil, then rinse them in water. You’ll want to look over each one for signs of iris borers (holes in the rhizomes) and soft rot. As you divide the rhizomes you’ll want to discard these sections and only plant the young, healthy rhizomes back into the ground. Using a sharp, sterilized knife, separate the rhizomes, making sure there are leaf fans on each section. Without the fan of leaves, the rhizomes are unlikely to grow. 

Once you have separated the iris rhizomes and discarded all of the infested or diseased irises, you will want to begin digging a shallow hole big enough for three to five iris plants in an area that receives at least 6 hours of full sun a day. You will want less than an inch of soil above the top of the rhizomes, so the hole doesn’t need to be deep. Cut the fan leaves about 4–6 inches long before planting. Plant bearded iris groupings about 24 inches apart to allow room for growth. Cover the roots, but allow the planted rhizomes to remain visible at the soil surface. 

Water newly planted iris rhizomes well, but do not continue to water unless it has been several weeks since the last rain. Keeping them moist will encourage rot. 

Once your new irises are established, apply a low-nitrogen fertilizer twice a year—in early spring—and just after the bloom to keep them healthy and happy.

Controlling Powdery Mildew on Vegetables

Every summer it seems to appear; white, powdery spots all over the leaves and stems of your vegetables. While it is rarely fatal, it can weaken susceptible plants and reduce vegetable and flower production. So what is that stuff exactly? 

Powdery mildew is one of the most widespread fungal diseases of plants, and also one of the easiest to identify. It appears as white or grey spots covering most or all of the surfaces of leaves. In the advanced stages, leaves can turn yellow, curl up, and drop off. This leads to stressed plants and reduced flower production. 

While it’s ideal to avoid an infestation by growing resistant varieties of plants, making sure your plants are in full sun, and preventing over-fertilization and crowding, there are things you can do to control powdery mildew that is already present. 

There are many commercial options for controlling mildew growth on plants. In particular neem oil is one of the many horticultural oils labeled for the control of powdery mildew as well as a number of other diseases. 

If you’re more of a DIY gardener, baking soda combined with dormant oil and liquid soap is also known to be helpful in the early stages of an infestation and will inhibit mildew growth.

In the very early stages, plain water will knock fungal spores off the plant before they can embed. Just be careful because wet plants can become the victims of a whole other host of diseases. When you water plants for this purpose, do so early in the morning so that the sun can burn off the water throughout the day. 

Potassium bicarbonate, which is similar to baking soda, is a contact fungicide that will kill powdery mildew spores on contact. 

Mouthwash mixed with water (in a one-to-three ratio) can eliminate mildew growth. Just be careful as it can burn new plant growth. 

Two to three tablespoons of apple cider vinegar mixed with a gallon of water can also be an effective anti-fungal treatment. 

These are just a few of the treatments available for powdery mildew. When treating an affected plant be sure to spray the entirety of the affected leaves including the underside of leaves. 

After treatment, you may want to trim off some of the most infected leaves so that the plant can put energy into new growth rather than into old damaged leaves. If you do go that route, you can take the plant debris and throw it away. You don’t want to put powdery mildew and its spores in your compost, as they can overwinter and spread to your plants next season. 

Should I Repot My Plants?

As you move your tropical plants outside for the summer, you may find yourself wondering if it’s time to repot a few of them.

There are several reasons to repot your plants. Sometimes, you just want to switch up your decor and put it in a new pot, and sometimes you may be concerned that the plant has outgrown its pot and has become root-bound. You may even have a plant that still fits in its pot, but has pulled all of the nutrients from the soil. In that case, you’ll want to “repot” by switching out the old soil for fresh potting soil. 

Generally speaking, you should repot indoor plants every 12 –18 months. Repotting is a good time to check on the health of your plant’s roots. Part of plant care is ensuring that your plants have a healthy root system and the only way to check on that is to repot your plant. 

When you’ve removed your plant from its pot, check the color of the roots. Look for any root rot (black, shriveled roots) and cut those pieces out. Gently shake the dirt off of the root ball and remove all of the old potting mix. Tease apart existing roots so that they can spread out in the new pot. If you have root-bound plants (a solid ball of root with little or no soil left) be careful when shaking out the root ball and spend extra time teasing the roots apart. A root-bound pot generally needs a larger pot; however, there are a few plants that like to be root bound. 

Peace Lily, Spider Plant, African Violets, Aloe, Umbrella Tree, Ficus, Agapanthus, Asparagus Fern, Spider Lily, Christmas Cactus, Jade Plant, Snake Plant, and Boston Fern all prefer to be root bound, so don’t repot them too often. 

When choosing a new pot make sure to look for a drainage hole. Ideally, when you water your plant you’ll do so thoroughly until the water runs through the bottom of the pot to keep salts and other minerals from building up in the soil. If your pot doesn’t have a drainage hole you may need to repot your plant more often. Remember that if you have a plastic pot or a sealed ceramic pot you’ll water your plant less often than if it’s in a terra cotta pot. 

After choosing your pot, make sure you have the right type of potting mix for your plant. If you have a cactus or succulent you’ll want a different type of soil than if you have a tropical foliage plant. Put a little bit of potting mix in the pot before carefully placing your plant in and filling in around it with new potting mix. Don’t compress the soil too much when repotting and water thoroughly. 

The whole process shouldn’t take you too long, and you’ll have happier plants when you’re done! So grab a plant, a new pot, and some potting soil and get re-potting! 

Brood X Cicadas Are Here, or Are They?

This May, all across the Eastern United States, a very special event will occur. Brood X periodical cicadas—a 17-year species of cicadas—will emerge. These insects have now spent 17 years underground feeding on tree roots and waiting for the soil to warm to just the right temperature. Historically, the emergence of these insects has been in decline, so this year will be an important marker to determine the health of the brood overall. 

Cicadas are harmless insects and provide food for all sorts of animals, but birds in particular. Their habit of emerging in force of numbers seems to have evolved as an evolutionary survival strategy.

Brook cicadas have one of the longest insect lifespans. The 13 or 17 years life cycle of these red-eyed insects is typically marked by their emergence from the soil. The cicada nymphs will head for tree branches to molt one final time, emerging as adults. This is when they begin singing their (extremely loud) songs. The song—which sounds like a very loud buzzing or screaming sound—can be heard until the very last of the adults has died and fallen to the forest floor. These songs bring the cicadas together to breed. The cicada life cycle has three stages: egg, nymph, and adult. Once the adults have joined to breed, the female cicadas will cut holes into tree branches and lay eggs inside. The eggs will remain there for six-to-ten weeks depending on the species of cicadas. Then tiny nymphs, about the size of a grain of rice, emerge and work their way down to the ground where they burrow for the next 13 or 17 years. 

Not all cicadas have such a long life cycle. 13-year cicadas and 17-year cicadas are called “periodic cicadas” or “brood cicadas” and have a long lifecycle while annual cicadas, as their name implies, only live for one year. 

There are 15 different broods of cicadas, which means that nearly every year some of these cicadas will hatch out and sing their summery song. While no one knows for sure when the annual cicada emergence will happen, the American Museum of Natural History lists May 13th as a likely start date for cicada season. So keep your eyes and ears open and if we’re all lucky, we’ll have a strong cicada season this year! If you see cicadas and want to help out scientists studying them, you can report periodical cicadas using the Cicada Safari App, available on the Google Play Store or the Apple Store.

Preparing Your Garden for Planting

Now that winter is finally over and the weather is turning warmer, it’s time to get your garden ready for planting. Robust plant growth isn’t an accident. Proper soil preparation is needed to ensure that vegetable gardens and flower gardens are productive as possible. 

The first step toward planting a garden, if you are planting it directly in the ground, is to do a soil test. What is your soil type? Is your soil alkaline or acidic? Most plants prefer acidic, loamy soils. Sandy soils and clay soils on the other hand can be more difficult to grow in; if you have these soil types soil amendments may be needed. One of the best ways to help prepare your garden is by adding organic matter to the soil such as grass clippings from the first mowing of the year, or compost. These organic materials will help with both nutrient delivery for your plants and will also ensure that the soil holds a proper amount of water. If you are an organic gardener you may choose to exclusively use this type of garden soil addition as fertilizer. 

Double digging may also help to prepare your garden for planting. When you double dig you are increasing soil drainage and aeration by loosening two layers of soil as you add in organic matter. This creates good garden soil for your plants to grow into and will help plant roots grow deep and strong. 

Early in the season cover crops may be a good idea to plant. A cover crop is a plant that you grow specifically for the soil. It’s meant to grow and be turned under into the soil instead of being harvested for your plants. Growing a cover crop can help ensure that you have good soil and that your soil for planting is full of available nutrients for your vegetables. 

In addition to planting directly in the ground, another good garden idea is to use raised beds. This means the soil is layered on top of your existing soil, generally within a frame. This can be done directly or in grow boxes. For these gardens, you’ll most likely purchase pre-prepared soil mixes that will come ready for use right away. They will have the proper nutrients available from the start and may make for an easier experience for beginning gardeners. 

What to Plant in March

Now that March is here the real work in your garden can begin. This month your garden comes alive with the end of snow and sleet, and the coming of warm weather. 

Early spring is the perfect time to get annual and vegetable seeds started indoors. Veggies—such as tomatoes, peppers, cucumbers, eggplants, melons, zucchini, basil, and other herbs—should be started early so they are well established by the time warm weather arrives. These vegetables tend to do best when you sow seeds indoors in pots rather than straight into the ground once it gets warmer. Once started they are easy to grow. Just give them lots of sun and water. Some plants don’t need to be started indoors. Asparagus roots, for example, are something that you should plant bare-root once the last frost date has passed, around mid-April.

Early potatoes can be planted from early March through April. These plants can tolerate a light frost but not a hard freeze, so mulch them to protect from the extreme cold if a late-season blast of cool weather should come up. Potatoes are cool-season vegetables and do best with temps below 80 degrees, so planting them in March gives you a nice head start. 

Broad beans and brussels sprouts take around 90 days to mature. Planting in March gives them a good head start. Brussels sprouts in particular benefit from maturing in cooler and even frosty weather. Leafy greens also prefer cooler weather, so as soon as the threat of a hard frost has passed, they should be planted in the ground. 

March is also a great time to plant fruit trees. Once the ground has thawed enough to dig a hole you’re safe to plant the tree. Don’t forget to water it well to help it settle into its new spot and you’ll have fruit in coming years. 

The Best Bulbs To Plant in February

While it may seem counterintuitive, winter can be a great time to plant bulbs. The bulbs you buy now are in a state of dormancy and, when planted properly, will not suffer damage from spending time in the ground over the winter. In fact, they may actually benefit from the chill. Many early spring flowers come from bulbs that require a chill in order to bloom. It is a belief among many gardeners that as long as the soil is workable there’s time to plant bulbs. Most bulbs prefer well-draining soil in full sun to part shade, so choose your location carefully. 

Tulip bulbs, lily bulbs, hyacinths, and more often require a period of chilling or they will not bloom the following season. Without a chill, they become annuals and die off. On the other hand, tender bulbs such as gladiolus bulbs need to be dug up before the true winter cold sets in or they will likely die off in a deep freeze. In hardiness zones, 4–7 early winter is an ideal time for planting spring-blooming bulbs. As a general rule spring-flowering bulbs should be planted in fall or winter, while summer flowering bulbs should be planted in the spring. When deciding which bulbs to plant when go by that rule and you will likely have success with your blooms.

Dig as deeply as you can when planting your spring bulbs and then cover the area with mulch to protect them. Don’t worry if you’ve already seen snow on the ground. As long as the ground itself is not frozen, they will likely grow roots. 

Plants like tulips, lilies, and hyacinths often look their best in naturalized plantings. So plant tulips and the like in a random pattern with irregular groupings for the most impact. Choose various shades of similar colors such as blue, purple, or white flowers for a more refined look, or mix them all together for an even more natural feel. 

These winter-loving bulbs often have blooms that make excellent cut flowers, so plant them thickly and they can be thinned out for bouquets without sacrificing the overall look come spring. 

January Gardening Activities

It’s a new year and your thoughts may be turning to your spring garden. That can seem far away during the dark days of January, but there are still plenty of things to keep you busy in the cold winter months. 

Winter is a good time to get organized for spring. Cleaning tools and going through seed catalogs for vegetable seeds are perfect snowy day activities. Be sure to put a thin layer of oil on your tools to protect them from rust. Choosing what plants you’ll grow and the layout of your spring garden is another good idea. Will you be planting right into the ground or into raised beds? If you’ve never tried raised beds before, read a couple of gardening books about their benefits; it may just give you a project for early spring! 

During winter trees and shrubs are at risk for being eaten by deer, particularly on Long Island, where the population is high and there are few natural predators. Hire a licensed company to apply a deer repellent spray to evergreens to deter munching. Speaking of sprays, using a dormant spray on trees and shrubs now can mean fewer pests and diseases during spring. Fruit trees in particular will benefit from this. 

January is a great time for planting bare root roses and bare root trees as well. These plants will be dormant this time of year and as long as the ground is workable it’s ok to put them into the ground. This will give them an early start before the heat of summer sets in. Rose bushes that are already established can be cut back in winter before new growth starts. 

While it may be too early in the growing season to sow seeds, you can still visit your local garden center and pick up the supplies you’ll need for sowing seeds starting in a month or two. This will give you time to figure out the lighting and location for your starter plants. 

Finally, if the lack of greenery is too much to bear, growing indoor plants can satisfy your green thumb. Miniature roses and poinsettias are popular this time of year, and love bright light or grow lights. These plants can bring a little floral pop to an otherwise grey winter day and help you make it through until the first crocuses of spring begin to pop their heads up above the soil.

Annuals for Cold Weather

The chilly weather is here but that doesn’t mean you can’t have some color in your garden. There are many flowers that come in a variety of colors that can handle a light frost and sometimes even a mild winter. Hardy annuals are easy to find in your local garden center, and they can extend the gardening season by months.

One of the most common cool-season annuals that you’ll see being sold are Pansies. Pansies come in almost every color of the rainbow and absolutely love cool weather. Planted in early fall or late winter, these cool-season annuals are champs at keeping color popping in your garden bed.

The Dusty Miller is another one of the frost-tolerant annuals. While they’re capable of surviving a light frost, once the first heavy frosts are expected it’s best to prepare them for the winter ahead. Trim them to about 4 inches tall and heavily mulch the plants to insulate them from the extreme cold of winter. Come early spring you can remove the mulch so your plants will be ready for another season of velvety growth.

Sweet Alyssum are annual flowers that can survive the cooler weather as long as there is no hard freeze. Made up of mounds of honey-scented, white blossoms, they add a snowy presence to the landscape and will, in the early part of the season, draw pollinators to your garden.

If you are looking for cut flowers in the winter season there are a few choices that can add color both inside and out. Winterberry comes in varieties with red, pink, or gold berries that look beautiful in arrangements. In addition to looking lovely, they also last long with an average vase life of 14 to 21 days.

Winter Heath blooms with lovely florets of pink, white, purple, mauve, yellow, or red. These can be cut in extremely long stems to add height to an arrangement.

Winter Jasmine blooms in mid-to-late winter with bright yellow blossoms. These can also be cut in long stems and bring a little joy to dark winter days.

Finally, Camellia is lovely in arrangements during winter. Their waxy rose-like blooms don’t tend to live long in a vase (about 3–5 days) but their unique and perfect beauty more than makes up for it!

How to Mulch Leaves

For many people, when the leaves fall it’s time to pull out the rake and the blower and start bagging leaves to be taken away. However, what you may not know is that by not raking leaves and leaving them on your lawn instead you can help enhance the soil and the effectiveness of your lawn fertilizer. 

It’s important not to leave whole leaves on your lawn as they can smother the grass, blocking the sun and eventually killing the lawn. Instead, you should run over those fallen leaves with a mulching mower. Most mowers have the ability to mulch if you use the right blade. A mulching blade is serrated rather than straight and helps to shred the leaves as you go over them. If you’re using a regular mower you’ll need to put on the mulching blade before starting your task. If you’re using a mulching mower you just need to raise the blade up as high as it goes and remove the grass catcher so that the shredded leaves go back onto the lawn. These leaves will break down over the course of the winter releasing nitrogen back into the soil. This nitrogen, in turn, will feed your lawn and help it to be as lush and green as possible. It will also help your lawn to fight off weeds like dandelions and crabgrass. Depending on how thick the tree cover around your property is you may have to mow once a week or so until the leaves stop falling.

As you mow over the leaves you’ll notice the pieces getting smaller and smaller until they sink down a bit between the grass blades. Once the grass is showing through, and the leaves are broken down to confetti size, you’re done with your lawnmower or mulching mower. 

If you want to use your fallen leaves as mulch for plantings rather than for lawn care you’ll still need to shred leaves first, though not as small as when you’re using them for the lawn. Even leaves destined for the compost pile should get shredded rather than remain as whole leaves. When you pile up whole leaves air and sunlight cannot get to the decomposing leaves, and it becomes worse once they get wet and soggy. Mold and diseases can grow in this anaerobic environment. Your mulch, like your compost pile, should be as fluffy as possible so that air can circulate and nature’s decomposers can do their work. The idea of leaf mulching is to protect the ground from freezing, thawing, and then re-freezing because this is damaging to plants. The leaf layer in this case serves as a temperature regulator to keep this from happening. You’ll want a thick layer of shredded leaves for leaf mulching your garden beds. 

So before breaking out the rake and the blower this year consider mulching your leaves instead. Your garden, and especially the soil, will thank you!