Shrub Tips


Azaleas & Rododenderons  Azaleas & Rhododendrons are one of the first signs of spring they have wonderful foliage the comes alive with blooms in spring.  Azaleas & rhododendrons are fairly easy to grow and care for as long as you remember a few key things.  One of the key things to remember about them is that they like a moist, rich soil but must not be overwatered. Overwatering will cause root rot and lead to a quick death.  It is advisable to amend the soil when planting to hold moisture but also to add sand, gravel, or pine bark to promote adequate drainage.  Another key thing to remember about rhododendrons & azaleas is correct placement in the landscape.  They prefer a location with morning sun and shade in the afternoon.  They also need to be protected from winter winds and soggy soil locations.  Rhododendrons & azaleas can be pruned in early summer after spring blooming has occurred (May or June), it is recommended not to remove the growth from the last year or two. If pruning is done at any other time of year, you will be removing your upcoming flush of flowers. If a more drastic pruning is needed it will have to be undertaken in steps.  If you remove too much of the foliage at one time it can disrupt the root ball to foliage ratio and leave the plant vulnerable to root rot. Its advisable not to remove more than a third or fourth of the foliage in one year and to make sure the plant has recovered before another drastic trimming is done. Rhododendrons respond well to an annual application of fertilizer.  It is advisable to apply this in a split dosage with half put down in march and the other half applied in June or July.  Make sure not to fertilize after July as this can lead to new growth in the fall that would be vulnerable to winter damage.  By splitting the application in half you provide nutrients for spring bloom in march and nutrients for plant growth and recovery in June and July.  We advise using Espoma Holly Tone to promote flowers and growth.  When applying fertilizer make sure to avoid contact with the roots as they are tender and can easily be damaged by fertilizer applied directly to them.

Cornus  Dogwood shrubs can be pruned up in late winter/early spring while still dormant. For shaping, trim about 1/3 off the branches. They can also withstand a rejuvenation pruning by cutting them all the way down to the ground to keep a neater and more compact appearance.

Deutzia  Deutzias are a neat deciduous plant with a great blooming habit in the early spring.  They are low maintenance plants with a punch of color.  Deutzias flower on old wood, so it’s advisable to trim the plant back hard after blooming in late spring. Doing so promotes new foliage and flowers for the next year.  Fertilize with Holly Tone in late winter/early spring before new buds break to promote even bigger flowers in the weeks to come.

Euonymous  You can trim and shape a burning bush to your liking in late winter/early spring while still dormant. If your burning bush has become large and overgrown, you can do a rejuvenation pruning just as leaves are emerging in spring by trimming the entire shrub down to 1-3 inches tall. 

Forsythia  Forsythia’s create an early pop of fantastic color in the spring. They are easy to care for and come in a range of sizes. Since forsythias bloom so early, one should hold off on pruning until after they bloom.  In late spring after blooming, the shrub may be cut down to over half to reduce size or reshape it. Because of the nature of the shrub they can be trimmed with a hedge trimmer.  Forsythia require little fertilizer but do benefit from a dose of Espoma Plant Tone in early spring to promote new growth and amazing blooms.

Hibiscus Rose of Sharon  These shrubs flower off of the previous years growth so they must be pruned in late fall, late winter, or early spring before buds form. Remove any dead or damaged branches as well as those that are growing in the wrong direction. Older and weaker branches should be removed to keep the plant open and airy. Trim back other branches to your desired shape. Be sure to remove any suckers that sprout near the base of the trunk. A rejuvenation pruning can be done to older plants by removing 2/3 growth. You might sacrifice some flowers for that year but it will benefit the plant's overall health. 

Hydrangeas  There are 6 main types, or classifications, of hydrangeas. 1. Big leaf or florist (macrophylla) 2. Panicle (paniculata) 3. Oakleaf (quercifolia) 4. Smooth (arborescens) 5. Climbing (petiolaris) 6. Mountain (serrata)

Hydrangeas are classified into these groups because of different flowering types, fertilizer requirements, and pruning times and severity.

   1. Hydrangea macrophylla - blooms on old wood and should not be pruned in the spring or you will be removing their flowers. They can be pruned after flowering but it is advisable not to prune unless necessary. There are series such as Let's Dance, Endless Summer, and Everlasting that will bloom on old & new wood so pruning can be done without fear of losing your flowers for the next year. 

   2. Hydrangea paniculata - blooms on new wood and can be pruned in the spring without worry of removing the blooms. When the blooms are finished, deadhead the spent blooms & shape it up how you like. 

   3. Hydrangea quercifolia - blooms on old wood and should not be pruned. If pruning is required do it shortly after blooming so the plant has time to reset buds for the upcoming season.

   4. Hydrangea arborescens - blooms on new wood and should be pruned in late winter and early spring with no worry of flower bud removal. 

   5. Hydrangea petiolaris - do not require pruning except to keep down their size, it is advisable to prune after flowering so flower buds are not removed.

   6) Hydrangea serrata - bloom on old wood so don’t trim them in the early spring.  They can be trimmed after blooming leaving enough time for growth and bud development for the next year. 

Hydrangeas all benefit from annual fertilizer applications.  An early dose of Espoma plant tone will help with blooming and overall plant health and it is advisable to fertilize in early spring and then again in early summer. Do not fertilize after August 1st, fertilizing late in the year can leave the hydrangea “soft” with new growth that can be damaged with winter cold.

Color Change - Only the big leaf (macrophylla) and mountain (serrata) can change their flower color in a predictable and controllable way. To change from pink to blue, one must add aluminum sulphate, which lowers the pH (5.2-5.5 is ideal) in the soil around the hydrangea. It's advisable to apply ½ once mixed with one gallon of water several times throughout the growing season.  Make sure to water in advance, as a heavy dose on a dry plant can burn the roots.  To change the flower from blue to pink, you must increase the pH to around 6.0-6.2 by adding dolomitic lime several times a year around the plant.  Use caution not to raise the pH above 6.4 which can cause an iron deficiency in the plants. Note - it is easier to change the flowers from pink to blue than blue to pink!

Lilacs Lilacs are known for their intoxicating fragrance in early spring along with a huge flush of color. They are relatively easy to grow and care for but do require pruning at a select time of year. Pruning should only be done directly following blooming, if pruning is done at other times you will remove the blooms. Pruning Lilacs on a regular basis helps to keep them from getting to tall and unmanageable.  When pruning, it's generally better to cut the entire stem than to just cut back the tops. Trimming lilacs is best accomplished using loppers or hand pruners.  Remove spent blooms all the way to the stem. This prevents seed production and encourages more blooms later on. You should cut back about a third of the branches. Cut away shoots growing near the ground that may be sprouting from the main trunk. This helps improve air circulation and light to filter through. If your lilac bush is already too large or becoming overgrown and unsightly it might take a drastic pruning to renew the shrub. You may need to reduce the entire bush to the ground (6 to 8”).  This is a drastic measure and will take up to three years before the plant has recovered to blooming size. Lilacs will bloom more and produce larger flowers with an annual dose of fertilizer. It is recommended to use Espoma Plant Tone early in the season just as buds break to help boost flower size and production.

Viburnums Viburnums are a favorite for landscaping, whether creating a hedge or as a specimen in the landscape.  They're easy to care for and feature wonderfully sweet smelling blooms.  Viburnums should be pruned after flowering so as not to remove upcoming flower production. Shape and thin to promote a healthy plant. If the plant has gotten too large, a renew thinning can be done, one can remove anywhere from 1 to 5 canes from the base (6-8”).  This, along with reduction pruning, can help bring a old oversized shrub back to life.  Fertilization with Espoma Plant Tone should be done in early spring to promote a large healthy plant with abundant flowers.

Weigela  These shrubs bloom on old wood and should be pruned right after flowering. To control its size, remove only 1/3 of the plants growth and should be cut back to where