Pruning Euonymus – How and When?

Euonymus is a large genus of plants which includes many species of deciduous and evergreen shrubs, trees, and vines.

Euonymus ‘Silver King’ is a beautiful variegated evergreen form.

Probably one of the most well-known of these is Euonymus alatus (Winged Euonymus, a.k.a. Burning Bush). This deciduous species is especially popular for its beautiful red fall color. Other popular species are the evergreen forms, Euonymus japonicus, Euonymus kiautschovicus, and the trailing Euonymus fortunei. Many of these evergreen cultivars have attractive variegated foliage.

Because of its diversity, euonymus has many different uses in the landscape. Some varieties are planted as stunning specimen plants, while others are used as an attractive living screen or hedge, and still other varieties create a lovely evergreen ground cover or trailing rock wall cover.

Burning bush in all its glory!

Few shrubs in the landscape provide brilliant fall color as reliably as the “Burning Bush” (E. alatus). When the temperatures begin to drop in the fall, this beautiful shrub transforms from a deep green to a striking fiery red. It’s no wonder these shrubs are so popular in the landscape – many even consider them overused! It should be planted in full sun to achieve the most intense fall color.

Unfortunately, Euonymus alatus and another popular deciduous species, E. europaeus, have escaped into the wild and have become invasive in some areas of the country.

Fruit capsules of E. europaeus will split open to reveal bright red seeds

The colorful fruit capsules which appear in the fall and add to their beauty in the landscape split open exposing equally colorful seeds. These seeds eventually drop to the ground and can produce hundreds of seedlings under the shrub or are eaten by birds and dispersed to other areas where they can germinate and grow.

The evergreen species, Euonymus japonicus, includes many of the more colorful variegated cultivars. Variegated cultivars should be planted in full sun to light shade for the best color.

Spreading euonymus (E. kiautschovicus) is a beautiful evergreen or semi-evergreen species with glossy dark green leathery leaves that is often grown as a hedge or living screen. ‘Manhattan’ is one of the most popular cultivars. Unfortunately, this species is prone to winter burn in colder zones.

Winter creeper, E. fortunei, is an evergreen species with a trailing habit which, depending on the cultivar, can be used as a ground cover, low shrub, rock wall cover, or as a climbing vine. There are many beautiful variegated cultivars in this species as well.

Finally – Pruning!

I originally began writing about euonymus because a few days ago I received a post on our discussion board about pruning these plants. I got a little off topic! Here is the question:

I have several overgrown Euonymus shrubs that have come into my hydrangea shrubs. I would like to cut the [euonymus] back but how far can I cut them and when is the best time?

How Much?

As far as how much they can be cut; these plants can really be pruned back as hard as you want or need to. Like many shrubs, euonymus has dormant buds in the bare wood and new growth will sprout below the pruning cuts so eventually you will end up with a beautiful, fresh, new but more compact shrub.

When?

The timing for pruning euonymus depends on the type, deciduous or evergreen – hence my discourse on the various species!

Euonymus alatus pruned to tree form.

Deciduous euonymus should be pruned in late winter or early spring before they start to leaf out. As I mentioned, these shrubs can be pruned hard if needed, even back to 3″ – 6″ from the ground. They can also be pruned less drastically, removing dead and crossing branches, thinning out about a third of the oldest stems (all the way to the ground), and pruning the remaining stems to create an attractive, natural looking shrub.

These euonymus can also be trained to grow as a small tree by pruning out all but 1-6 main stems and removing any lower branches that develop along these main stems.

The pruning time for evergreen euonymus depends on how hard you need to prune them. If they need to be cut fairly hard to rejuvenate them or to bring them down in size if they have grown too large for your space, this should be done in late winter or early spring while they are still dormant.

If you just need to prune them back to shape them or reduce their size a little, you can prune them in the late spring or early summer when they are growing. It is best to avoid pruning them after the end of July or any new growth will not have time to harden off before winter.

Remember

If you need to do any “severe” pruning of your other shrubs like holly, boxwood, rhododendron, or yew, now (while they are still dormant) is the time to do it.

Be sure to fertilize them with Espoma Holly-tone, Plant-tone, or Tree-tone after you prune!

Until next time – Happy Spring!

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Grafted Vegetables – The Future of Vegetable Gardening?

When I first heard about grafted tomato plants several years ago, I thought the idea was crazy. I was very aware of the great cultural benefits of grafted trees and shrubs but why in the world would you spend the time and effort to graft a vegetable that only grows for a season then dies with the first frost?

Grafted tomato; Cornell University Cooperative Extension

It didn’t dawn on me at the time that the same disease resistance and increased overall vigor that the rootstock imparts to a grafted fruit tree could also work for a grafted tomato plant. When you think about it, this is a brilliant concept because tomatoes and many other vegetable crops have a plethora of disease and pest problems that we as gardeners are constantly battling.

It turns out that grafting vegetables is not a new practice at all – they’ve been doing it in Asia for a long time!

What is grafting?

Grafting involves taking the top of a plant (the scion) that has very desirable fruit qualities like superior taste (but low vigor and disease resistance) and attaching it to the bottom of a plant (the rootstock) that is known for its vigorous growth and disease resistance.

Getting ready to graft a melon (scion)
to a gourd rootstock at Merrick Farm,
Wilbraham, MA  Photo: Megan Poljacik

One of the main advantages of grafted vegetables is their resistance to soil-borne pests and diseases.

Remember my whole diatribe on crop rotation? There are a lot of people with small backyard gardens that don’t have the space to rotate their crops. Planting grafted vegetables reduces the need for crop rotation. The rootstock that is used for the graft is selected for its resistance to a wide range of soil-borne diseases, including those that persist in the soil for many years. So even if diseases like Verticillium wilt, Fusaruim, bacterial wilt, or tobacco mosaic virus are lurking in your soil, grafted tomatoes are less likely to be affected because of their vigorous, disease resistant rootstock. You have a super plant!

Completed melon graft; Merrick Farm, photo: Megan Poljacik

What about diseases like early blight and late blight that travel to the plants via wind and rain? Are grafted plants protected from these devastating diseases? Unfortunately, these diseases attack the above ground parts of the plants – the foliage, stems, and fruit and the rootstock of grafted plants cannot directly provide resistance to these foliar diseases. However, as I have said many times before, healthy, vigorous plants are much less susceptible to disease and pest pressure.

An heirloom tomato grafted on a superior rootstock will theoretically be more vigorous, healthy, and productive than if it were growing on its own roots. The root system of the “super rootstock” will be much more extensive, thus providing more surface area for absorption of water and nutrients. This should lead to a healthier plant. Many of the grafted tomatoes that you will find are heirloom varieties. These very tasty tomatoes can be more prone to disease problems than hybrid tomatoes so grafting may offer a healthier, more productive plant.

Conversely, if a blight resistant tomato such as Defiant is grafted onto a hearty, disease resistant rootstock, you could end up with a seriously disease resistant tomato! Actually, this is a popular grafted tomato that is available!

Tips for growing grafted tomatoes

Grafted tomato planted with the graft well above the soil line.

Remember how you have always been told to plant your tomatoes as deeply as possible because they will develop roots all along the buried stem and you will end up with a more robust plant? Deep planting is a no-no for grafted plants. It is extremely important to keep the graft above the soil line when you plant. If the graft ends up below ground, roots will develop above the graft, which totally defeats the purpose of having a grafted plant! When the scion roots into the soil, the disease resistance of the rootstock is bypassed and the plant is no longer protected. Money wasted! This may be the reason why some people are not successful with grafted plants and feel that they are not worth the expense to purchase.

Keep the graft at least an inch above the soil when you plant.

As the plant grows, provide it with a good support system to keep it off the ground. Any stems or branches that touch the ground can take root – again, bypassing the disease resistance of the rootstock. We grow our tomatoes on a trellis and keep all the side shoots tied up as well as the main stem. You can also tie them to stakes or a fence or grow them in cages – anything that keeps the plant from sprawling on the ground where it can take root.

It is also important to remove any growth that develops below the graft.

Many different vegetables are being grafted these days.

Melons are commonly grafted to improve disease resistance and yield.

Although tomatoes are the most common, you can also find (or create your own) grafted peppers, eggplants, cucumbers, squash, melons, and watermelons. Each of these is grafted onto vigorous rootstocks that are developed specifically for that particular vegetable type and the specific diseases that attack it.

Grafted vegetables not only have increased vigor and resistance to soil-borne diseases but, because of the superior root system that develops in these plants, they also show an increased tolerance to environmental stresses like drought, temperature extremes, and nutrient deficiencies. The extensive root system increases the area that the plant can exploit for the water and nutrients needed for growth. The result is a healthier plant that not only bears well, but potentially requires less fertilizer, is drought tolerant, and has a reduced need for pesticide applications.

This may be the year that we give grafted plants a try. We may try to pick up a tomato plant or two at a local garden center. It will be especially interesting if we can find a grafted version of one of the varieties that I plan to grow from seed. That would be a cool experiment! I will keep you posted!

Until next time – Happy Gardening!

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