There are over one thousand species of mistletoe worldwide. These photosynthetic evergreen shrubs are classed as parasitic plants as they usually attach themselves and grow on the branches of other trees via a root-like structure called a haustorium.
The two most well-known species of mistletoe are Phoradendron leucarpum (commonly known as American mistletoe) and Viscum album (European mistletoe), as these are both commonly sold around Christmas time. As you would expect, the American mistletoe plant is more readily available in the United States, so this is the one that this article will focus on.
It is worth noting that American mistletoe is also sometimes known by the botanical names Phoradendron serotinum and Phoradendron flavescens, and these names are used interchangeably with Phoradendron leucarpum.
American mistletoe plants can be found growing on many varieties of deciduous trees, but they are commonly seen on elms, swamp tupelo and river birch, amongst others. Despite one of its other common names being oak mistletoe, they don't very often inhabit this species.
As the haustorium establishes and grows, the mistletoe will start to develop into a ball-shape (often referred to as a witches' broom), and they have been known to reach in excess of 100 pounds in weight and be up to one meter in width. It is the female form of mistletoe that produces the famous white berries in winter that this plant is famous for. These berries turn into a pulp as they ripen and this sticky concoction clings to feeding birds, and they are responsible for the dispersal of the seeds that result in germination occurring on new trees. Interestingly, the old English translation of mistletoe means "twig dung".
Unless you plan to grow mistletoe specifically for a festive harvest, this isn't usually a plant that is encouraged in gardens. The balls, while slow-growing, tend to look unsightly rather than ornamental or interesting, and their growth habits can be harmful to the trees they are attached to.
These slow-growing and persistent plants rarely seriously harm or kill the trees they are inhabiting. In some cases, however, they can cause disfigurement and impact on vigor and health.
If a mistletoe plant does start to grow on one of the trees in your garden, providing you have a healthy host, and you keep the ball in check, it will give you a lovely traditional decoration for the festive season.
These plants also make an excellent food source for various wildlife, and it could encourage them to visit your garden. Butterflies, bees, and other pollinators are also attracted by the nectar and pollen of the insignificant flowers.
|Botanical Name||Phoradendron leucarpum|
|Common Name||American mistletoe, Oak mistletoe, Eastern mistletoe|
|Plant Type||Shrub, Evergreen|
|Mature Size||Up to 1m. tall and 1m wide|
|Sun Exposure||Partial Shade, Full Shade|
|Bloom Time||Late winter to early spring|
|Flower Color||insignificant green flowers followed by white berries|
|Hardiness Zones||5 - 9, USA|
|Native Area||North America|
|Toxicity||Toxic to people and pets|
If you do decide you want to grow your own batch of mistletoe for kissing under, you will first of all need to have a healthy host tree specimen, and it will need to be a species that the plant is known to grow on. The hemiparasitic mistletoe relies on the host it lives on for water and mineral nutrients.
The tree needs to be well-established and should be at least twenty years old.
American mistletoe plants can cope with shady environments, but they do best in a sunny or semi-shade position. This is because they gain additional nutrition from the process of photosynthesis.
This semiparasitic plant gains its water and much of its mineral nutrients from the host tree. No additional watering will be required.
Temperature and Humidity
This leafy mistletoe variety needs temperate conditions to survive. Regions that experience harsh, sub-freezing temperatures or exceptionally dry conditions are not going to be suitable for growing this plant. In the wild, they tend to be found in low-lying ground zones that are fairly humid.
Is Mistletoe Toxic?
While Native Americans used this mistletoe species to treat a variety of ailments, the leaves, berries, and stems are all toxic when ingested. They contain a compound called phoratoxin and consuming large quantities could have a serious impact, for children or pets.
Some people can also have a dermatitis skin reaction to the plant, so it may need to be harvested using gloves.
Toxicity of Mistletoe: Symptoms of Poisoning
The symptoms of ingesting too much phoratoxin can include the following:
- Gastric discomfort
- Blurred vision
- Lowered blood pressure
- Slowing pulse rate
Pruning back mistletoe balls will help to ensure they do not become too heavy and too much for the branches of the trees they are inhabiting. If an unwanted mistletoe ball appears on a tree in your garden, you will have to cut it right back to the roots and then cover the remainders with black plastic to kill it off permanently.
Propagating Mistletoe Plants
Mistletoe propagation can be tricky. You need the right conditions and a suitable tree host. The berries then need to be squashed into the lower side of a strong and healthy branch between late fall and early winter. After this, it is just a case of waiting until the spring to see if germination is occurring.