- Propagation Of Holly Shrubs With Holly Cuttings
- Propagation of Holly Shrubs
- How to Grow Holly Cuttings
- How to Propagate Holly Bushes
- Water Works: Rooting Cuttings in Water
- How to Propagate Holly Trees
- Plant Propagation by Stem Cuttings Instructions for the Home Gardener
- Procedures for Rooting Stem Cuttings
- Holly Bushes
Propagation Of Holly Shrubs With Holly Cuttings
Holly cuttings are considered hardwood cuttings. These differ from softwood cuttings. With softwood cuttings, you would take tip cuttings from the branch ends. When you are propagating holly bushes, the holly cuttings are taken from that year’s new growth.
Propagation of Holly Shrubs
Holly cuttings are made from canes of new growth that have been removed from the holly bush. Once you have these canes, you can cut them into pieces about six inches in length.
Propagating holly should be done while the bush is dormant. If your holly is deciduous, this means your cuttings won’t have any leaves on them. Although they have no leaves, you will see bumps on the canes. These are known as bud unions. This is where the following year’s leaves are going to grow from. For evergreen hollies, you will take cuttings when the weather is cold and you should remove all but the top two sets of leaves from the cuttings. The bud union on evergreen hollies will be where the leaves meet the stem.
When you are propagating holly and removing a piece from the plant itself, you should cut at the bottom just below one of the bud unions. Then, from this piece you will partially cut about three quarters of an inch above another bud union, which should give you a good 6 inches of cutting that can be planted.
Following this procedure will help you know which is the top end and which is the bottom planting end of the holly cuttings. This also helps because the cuttings are now considered “injured” and an injured plant will develop roots where the callous develops over the injury to the holly bushes.
How to Grow Holly Cuttings
Growing holly cuttings is not at all difficult. You will simply take your cuttings and dip them in a compound used for rooting. There are various strengths to the rooting compound and your garden store can let you know which one you need for growing holly.
For deciduous types, take your dipped cuttings and line them up so the ends that are dipped are even. This way you can take the cuttings and tie them into bundles.
You will want to plant your growing holly in an area in your garden that receives full sunshine. Find that area and dig a hole that is at least 12 inches deep. Make sure your hole is large enough to hold all of the bundles you have made of the cuttings. Put these bundles into the hole upside down. There is a reason for this.
You want the butt end of the cuttings facing upward. Make sure you completely submerge your growing cuttings in the ground, about six inches below the surface. Cover these cuttings with soil completely. You do not want any part of the growing holly cuttings to be sticking out of the soil.
Make sure you mark your growing area with a stake so you can find them when you start gardening in the springtime. You also might want to use moist peat to cover the cuttings with before you put soil over them.
In the springtime, you will see holly bushes appearing. You can transplant them or leave them right where they are.
*Alternatively, you can simply plant the cuttings (without burying them) as soon as you take them in late fall, or whenever the ground is not frozen.
For evergreen types, stick the ends treated with rooting hormone about 3/4 to one inch deep in a medium of coarse sand – in a suitable area outdoors. These will need to be watered frequently throughout fall, as the sand will drain quickly. Unless your winters are particularly dry, there’s no need for watering during this time, especially if you get snow.
Resume watering in spring and continue throughout summer. This method works best if the cuttings are left until the following spring, at which time there should be adequate root growth for transplanting elsewhere.
How to Propagate Holly Bushes
holly bush image by Sunshine Photos from Fotolia.com
Propagating holly bushes through woody stem cuttings does not require any special equipment. Through proper selection and cutting the correct stem, a seedling will grow that can be transplanted the second year growing season. While the holly bush is a broadleaf evergreen, propagation must take place during the late summer to winter months. According to Washington State University, taking a semi hardwood cutting from the holly bush has a moderate to high probability of taking root.
Select last year’s growth on the holly bush mother plant, during late summer into the early winter months. Cut a 6- to 8-inch-long stem from the end of the plant.
Remove the lower leaves, 2 to 3 inches from the cut end.
Dip the cut end into the rooting hormone powder. Allow the white powder to coat the entire lower end where you removed the leaves.
Mix equal parts of peat moss and sand as the potting soil medium. Fill a 6-inch-diameter pot, with bottom drainage holes, to within 1 inch of the top rim of the pot.
Push a pencil into the soil to form a hole for the placement of the holly bush stem cutting. Insert the cut end of the stem cutting into the preformed hole. Avoid removing the rooting hormone powder from the cutting when placing it in the hole.
Firm the soil around the cutting. Water the potting soil to moisten. Keep the soil medium moist, but not overly wet.
Place the pot in a warm location out of direct sunlight. Inspect daily, remove any dropped leaves from the soil surface, and keep moist.
Tug on the holly cutting after two or three months from initial planting. If you feel resistance, the stem cutting is taking root.
Water Works: Rooting Cuttings in Water
A few of the herbs didn’t respond at all. French tarragon (Artemisia dracunculus var. sativa), thyme (Thymus vulgaris ‘Provencal’), balm of Gilead (Cedronella canariensis), and myrtle (Myrtus communis) either rotted or had failed to root after two months. Two cultivars of common sage, S. officinalis ‘Rubriflora’ and S. o. ‘Albiflora’, did not root at all. (All of these can be propagated by division or are fairly easily rooted in a peat-based medium that is misted frequently.) I found that not all varieties of the same herb species rooted with the same speed or vigor, but this is also true with other propagation methods.
Some techniques that improve the rooting of cuttings in other media don’t work when used with water. Scented geraniums, for instance, often root better when they are cut in the evening and allowed to sit in a plastic bag overnight to allow the wound to callus before they are stuck in a soilless medium. The cuttings that I treated this way did not root at all in water, while untreated ones did well. I knew that wounding cuttings of sweet bay (Laurus nobilis) by scraping either side of the stem helps them strike roots in a peat-perlite medium, but this didn’t seem to make any difference in water.
The response of bay cuttings surprised me. Even under the most favorable conditions—with root-zone heating and intermittent misting—only 50 to 70 percent of my woody bay cuttings will root in a soilless growing medium after six to eight weeks. I tried them in water, and they just sat in their Styrofoam cups without striking a single root. At the end of two months, the stems didn’t appear callused, swollen, or ready to sprout roots, but the part of each stem that was under water was covered with wartlike nodes. I nearly gave up on them, but instead I moved them to 2 1/2-inch pots containing my usual growing medium. Within a month, all were nicely rooted and growing well with no special care. A 100 percent success rate with bay cuttings was a first for me.
Although it’s quite possible to throw a cutting in a glass of water and have it root, you’re likely to have greater success with a wider range of cuttings if you pay attention to a few details. Take cuttings from plants that are in vigorous growth outdoors. Indoor plants with soft, thin stems are unsuitable for rooting; outdoor plants that are dormant or entering dormancy are often difficult or impossible to root. Generally, the best time for rooting cuttings is in spring, but I have had success with cuttings taken all through the growing season. Nonflowering stems are the best choice; remove any flower buds from other stems.
Choose plants that are free of diseases and insects. Take cuttings in the same way you would if you were rooting them in a soilless medium. As a hedge against failure, I like to cut several stems of each plant, putting them all in one container unless they seem overcrowded. Cut each stem about 3 to 4 inches from the tip with a sharp pair of scissors or knife and remove the lower leaves on the part that will be submerged. Fill a glass, short jar, Styrofoam cup, or other container with water to just below the first leaves; at least the top third of the cutting should extend above the rim. Place the containers where they will receive plenty of bright light but no direct sun; I rooted my cuttings on the kitchen windowsill.
Changing the water every day is the key to success with rooting in water. It keeps the water free from bacteria that can cause stems to rot.
As soon as the cuttings have roots 1/4 to 1/2 inch long, they are ready to transplant into pots; don’t let them grow into a dense tangle. For growing medium, I recommend using a peat-based mix. You can purchase a prepared mix such as Pro-Mix BX, or make your own by mixing equal parts of peat and perlite and adding the equivalent of 1 teaspoon lime per 6-inch pot; dampen the mix with a half-strength fertilizer solution.
I have read so often that cuttings rooted in water do not transplant or grow well, but I have never had any problems as long as I first transplant them into a pot so that they can become established plants, a system I also follow with cuttings rooted in a soilless mix.
Place the potted cuttings in a sunny window or a few inches below fluorescent lights or in a greenhouse. The heat in my greenhouse (often over 100°F during the day) made my cuttings grow quickly. Pinch the stem tips to promote branching after you pot them. Continue to fertilize with a half-strength fertilizer solution every fifth time you water.
Let the cuttings grow on for several weeks before transplanting them to a larger pot or into the garden. The roots should be visible and hold the root ball together.
Rooting cuttings in water is a handy propagation technique for use throughout the growing season, but it is especially useful in late summer when it’s time to start new plants to grow indoors over winter. With luck and a little attention, you’ll have windowsills filled with rooted cuttings to enjoy during the cold months or to set out next spring, as well as some to share with friends.
Tom DeBaggio is an herb grower in Arlington, Virginia, where he owns a seasonal retail greenhouse. This article is adapted from a chapter in his book, Growing Herbs from Seed, Cutting, and Root, which will be published in November by Interweave Press.
“Deck the halls with boughs of holly” may be a traditional Christmas carol, but holly has enjoyed a long symbolic history in other cultures as well. From decorating statues of Saturn—the Roman god of the harvest—to providing medieval protection from evil spirits, to offering shelter to imaginary woodland creatures and fairies, holly boughs and berries have brightened up the winter months since ancient times.
In the garden, hollies (Ilex sp.) are a striking choice that provide year-round interest and serve as great foundation plantings or hedges. There are hundreds of varieties of hollies, ranging from tiny shrubs less than a foot tall to towering trees reaching 70’. Most are hardy to zones 5 or 6, with a few varieties hardy to zone 4.
Hollies are known more for their berries than their small white flowers. You can find red, pink, blue, orange, yellow, and white berries, with some varieties more showy than others.
The shrubs and trees themselves may be rounded, pyramidal, columnar, or weeping in form. Leaf shapes range from the large, spiny leaves of holiday tradition, to tiny, smoother ones that are often mistaken for boxwood.
Sorting out the hundreds of varieties and hybrids of hollies can be a dizzying task. In general, hollies can be divided in the following main groups:
- English Holly: (Ilex aquifolium) These are the varieties most commonly associated with the Christmas holiday. With glossy, spiny foliage and variegated options, they can make a bold statement both indoors and out. Popular varieties include ‘Angustifolia’ and ‘Gold Coast.’
- American Holly: (Ilex opaca) Similar to English holly but with duller leaves. The trees tend to be pyramidal in shape and make great barrier plants. Common varieties include ‘Carnival’ and ‘Greenleaf.’
- Japanese Holly: (Ilex crenata) Include the distinctive ‘Sky Pencil’ as well as dwarf spineless varieties such as ‘Yaupon’ and ‘Helleri.’
- Chinese Holly: (Ilex cornuta) Best known for the large, glossy, spineless varieties such as ‘Burford’ and ‘Carissa.’
- Hybrid Holly: Includes countless options, one of the most popular being the Meserve hybrids (Ilex x. meserveae) which cross English and Chinese hollies with the more cold-hardy ‘Prostrate (I. rugosa) variety. Popular Meserve hybrids include the Blue hollies and ‘China Girl.’ A common natural American holly hybrid is ‘Fosteri’ (I. x attenuata).
- Deciduous Holly: These varieties lose their leaves to display branches laden with berries in winter, giving rise to the common name of Winterberry (I. verticillata), as well as Possumhaw (I. decidua). Popular varieties include ‘Red Sprite’ and ‘Jim Dandy.’
- Miscellaneous Evergreen Varieties: As if those above weren’t enough, there’s Inkberry (I. glabra) as well as Asiatic varieties such as Longstalk (I. pedunculosa) and Perny (I. pernyi).
Plant Gender and Berry Production
Hollies have male and female plants, with only the females producing berries. Female plants must be pollinated by male plants that bloom at the same time.
In developed neighborhoods, there are often sufficient male shrubs in the vicinity, but if your plant is not producing berries you may need to plant a pollinator. A good guideline is that you need at least one male plant for every ten females. Many cultivated varieties have male and female named counterparts, such as Blue Girl and Blue Boy.
Some commercial growers solve the pollination problem by grafting together both male and female stems, or by planting them together in the same pot. Be sure you know the plant’s gender before purchasing a holly shrub, so you won’t be disappointed.
‘Helleri’ reaches 4’ tall and resembles a small boxwood
Tips for Growing Holly
- Hollies don’t transplant well, so consider the plant’s full-grown size when choosing your planting spot.
- This also means it’s difficult to transplant one from the wild, so buy nursery-grown plants instead.
- Hollies can be propagated from cuttings of year-old growth. Propagation from seed is difficult but not impossible.
- Plants usually bloom within 2-3 years. Berries may take longer, so be patient!
‘Soft Touch’ is a dwarf spreading variety that grows only 2’ tall but up to 8’ wide.
Planting and Growing Conditions
While many of us go on a mad search for holly branches and berries around the holidays, holly shrubs are best planted in spring, right before they start growing but with plenty of warm weather on the way. Hollies like:
- Light: Holly plants to best in full sun.
- Soil: Well drained loamy soil that is slightly acidic. If your soil is very heavy, add some organic material to lighten the texture and improve drainage.
- Water: Hollies like a moderate amount of water, usually adequately provided by rainfall. Water weekly during drought.
- Mulch: Several inches of mulch to prevent freeze-thaw damage to the shallow roots. Apply mulch in a circle as wide as the branches.
- Fertilizer: A dose of fertilizer in spring and fall can help keep plants healthy.
Hollies respond well to pruning and make great hedges or geometric shapes. Correct bare spots, caused by over shearing, by occasionally making deeper pruning cuts to allow light to penetrate the plant.
Take care to prune branches only back to a growth bud – if you completely remove a holly branch or stem, it may not fill back in. The holidays are a great time to prune hollies – then use those cuttings to deck the halls!
The striking tall column of ‘Sky Pencil’ make it a good container plant.
Pests and Diseases
- Birds love holly berries, but thankfully they prefer them after several freezes, which usually means they wait until late winter to eat them.
- The most common diseases affecting hollies are black spot, phytophthora leaf and twig blight, and sooty mold.
- Problematic insects include holly leaf miners, bud moths, and red mites.
- How to Prevent Holly Leaf Spot (article)
- Pruning Bare Branches on Holly Bushes (article)
- Brighten Up Your Winter Garden with Berries (article)
How to Propagate Holly Trees
Holly trees are used to make popular Christmas door decorations because of their glossy leaves and bright red berries. Holly can be grown as a tree, plant or shrub and will make a welcome addition to any garden as they thrive in dry, acidic soil with good drainage. Propagation is a low cost but lengthy process that can often take several years but it is easily achieved using holly cuttings or holly seeds.
Holly trees can be either male or female. The female trees will produce red berries in the winter, whilst the male ones will not. Both holly types will flower in the spring. A male holly tree can pollinate up to three female trees. Male holly trees do not have to be planted next to female trees, but as long as they are close to the female ones then healthy pollination will take place.
To propagate holly tress from seeds is a time consuming process which will require a lot of care and attention. It can take up to three years for holly trees to grow from seeds and then up to another three years for the developing trees to produce any flowers.
Collect several of the holly berries, these are the seeds. Break the skins off the berries and then rinse them in cold water. Place the washed holly seeds into an empty planting pot, and then cover the seeds with soil. The holly seeds will need to be placed in a cool area. Once the holly plants have started to grow roots they can be transplanted into pots to allow them to thrive and develop further. The holly trees will need to planted in acidic soil and watered on a regular basis for the first year. In the second year of growth transplanting can take place during the spring months. After a year in pots the young holly trees will be ready to be transferred to the garden. Ensure that there is one male holly to every three females.
Growing holly trees from cuttings is probably the simplest and most popular method of propagation. For the best results holly cuttings need to be taken a quarter inch below the leaf node, and this should be done in the late spring or summer months.
Once the holly cutting has been selected remove all excess leaves, then place the tip in water until it can be potted. Fill a planting pot with acidic soil; apply rooting hormone powder to the cutting before planting it upwards into the pot. The potted holly tree will need to be kept in a cool area, it can be stored outside if the winter is not too harsh. During spring leaves should start to grow on the young holly tree. If no leaves grow then either wait until next winter or start the process again with a new holly cutting. When leaves have grown on the young holly tree it can be transplanted the following spring. Ensure that there are three female trees to every male.
Plant Propagation by Stem Cuttings
Instructions for the Home Gardener
Procedures for Rooting Stem Cuttings
Skip to Procedures for Rooting Stem Cuttings
Cuttings should generally consist of the current or past season’s growth. Avoid material with flower buds if possible. Remove any flowers and flower buds when preparing cuttings so the cutting’s energy can be used in producing new roots rather than flowers. Take cuttings from healthy, disease-free plants, preferably from the upper part of the plant.
The fertility status of the stock (parent) plant can influence rooting. Avoid taking cuttings from plants that show symptoms of mineral nutrient deficiency. Conversely, plants that have been fertilized heavily, particularly with nitrogen, may not root well. The stock plant should not be under moisture stress. In general, cuttings taken from young plants root in higher percentages than cuttings taken from older, more mature plants. Cuttings from lateral shoots often root better than cuttings from terminal shoots.
Early morning is the best time to take cuttings, because the plant is fully turgid. It is important to keep the cuttings cool and moist until they are stuck. An ice chest or dark plastic bag with wet paper towels may be used to store cuttings. If there will be a delay in sticking cuttings, store them in a plastic bag in a refrigerator.
While terminal parts of the stem are best, a long shoot can be divided into several cuttings. Cuttings are generally 4 to 6 inches long. Use a sharp, thin-bladed pocket knife or sharp pruning shears. If necessary, dip the cutting tool in rubbing alcohol or a mixture of 1 part bleach to 9 parts water to prevent transmitting diseases from infected plant parts to healthy ones.
Remove the leaves from the lower one-third to one-half of the cutting (Figure 4). On large-leafed plants, the remaining leaves may be cut in half to reduce water loss and conserve space. Species difficult to root should be wounded.
Treating cuttings with root-promoting compounds can be a valuable tool in stimulating rooting of some plants that might otherwise be difficult to root. Prevent possible contamination of the entire supply of rooting hormone by putting some in a separate container before treating cuttings. Any material that remains after treatment should be discarded and not returned to the original container. Be sure to tap the cuttings to remove excess hormone when using a powder formulation.
The rooting medium should be sterile, low in fertility, and well-drained to provide sufficient aeration. It should also retain enough moisture so that watering does not have to be done too frequently. Materials commonly used are coarse sand, a mixture of one part peat and one part perlite (by volume), or one part peat and one part sand (by volume). Vermiculite by itself is not recommended, because it compacts and tends to hold too much moisture. Media should be watered while being used.
Insert the cuttings one-third to one-half their length into the medium. Maintain the vertical orientation of the stem (do not insert the cuttings upside down). Make sure the buds are pointed up. Space cuttings just far enough apart to allow all leaves to receive sunlight. Water again after inserting the cuttings if the containers or frames are 3 or more inches in depth. Cover the cuttings with plastic and place in indirect light. Avoid direct sun. Keep the medium moist until the cuttings have rooted. Rooting will be improved if the cuttings are misted on a regular basis.
Rooting time varies with the type of cutting, the species being rooted, and environmental conditions. Conifers require more time than broadleaf plants. Late fall or early winter is a good time to root conifers. Once rooted, they may be left in the rooting structure until spring.
Newly rooted cuttings should not be transplanted directly into the landscape. Instead, transplant them into containers or into a bed. Growing them to a larger size before transplanting to a permanent location will increase the chances for survival.
Figure 4. Remove the leaves from the lower one-third to one-half of the cutting.
Figure 4. Remove the leaves from the lower one-third to one-half of the cutting.
The Holly shrub, botanically known as Ilex, is a genus comprising of about 400 species. Holly is an ancient plant that has been used by former civilizations for decoration and ceremonial reasons. The holly plant, with the shiny dark green leaves and prickly edges have been mentioned from pagan times when the Druids adorned themselves with holly as they entered the woods.
Holly also has had a long connection with Christmas. Some of the first Christians decorated their homes with ‘Boughs of Holly’. Today, hollies are widely used as ornamental plants and have been developed for gardens.
Hollies range in size from less than 1 foot to plants over 70 feet tall. They are popular because of their dark, evergreen leaves and their production of berries which are usually red. Holly berries are not edible for humans. Birds and some other small mammals will eat them after they go through the freeze and thaw process several times. The Holly berries sustain many species of birds in late winter when food is scarce.
Hollies like to be planted full sun and well drained, acidic soils. Prune hollies to optimize more leaf production. Prune them in late summer throughout fall and winter. We offer several varieties of holly. Click the photos to learn more, or call our plant experts at (888) 864-7663.