Hydrangeas are perennials that grow from seed. They have many names such as water lilies, sea roses or sea lily. Most commonly they are known as the blue flowers because of their color. The name “blue” comes from the fact that they look like a blue flower petal with purple center (see image). These plants come in all shapes and sizes; some are small shrubs while others reach up to 10 feet tall!
The plant grows best in moist soil but will tolerate dry conditions. They prefer full sun and do well under artificial lighting if it provides them with enough light. They are drought tolerant so long as they get plenty of moisture during the day. Some varieties bloom from spring through fall, while other varieties bloom throughout the year. The plants are very hardy plants and can survive harsh winters and hot summers without any problems.
Why Is My Hydrangea Not Blossoming?
A common problem when it comes to hydrangeas is that they don’t bloom until the last few days before frost. Other reasons include:
Too much shade – Too little sunlight – Poor drainage – Overwatering/Under watering – Lack of humidity – Too much fertilizer/irrigation – Excessive heat/cold – too cold – too wet – too dry – lack of air circulation around the plant.
If your hydrangea is not blooming as much as it could, chances are that one of the above issues is affecting it. Follow the tips below to help ensure your plant grows as best as it can.
1. Too Much Shade
This usually isn’t an issue if you recently planted your plant in the ground or a pot. If you’ve had it for several years, chances are that it doesn’t get as much sunlight as it could. Move it into a spot that receives more sunlight. If this isn’t possible, there may be other issues such as poor drainage or the plant might need to be dug up and moved to a new location.
2. Poor Drainage
If your soil is not draining water effectively, this is an important problem to fix right away. Your hydrangea will not survive in soil that holds water for long periods of time. Either the roots will rot or it won’t get enough nourishment to grow and thrive.
One way to tell is if your plant sits in a saucer shaped pool after it rains. This means the soil is not draining properly, which could be caused by several factors. Your soil might contain too much sand, loam or clay. It could be mounded up too high or contain puddles after a heavy rain.
You can fix drainage problems by digging out some of the soil and mixing it with sand, loam or peat moss. If this doesn’t work, your only option may be to replace the soil with something that has better drainage.
These are two distinct problems that can have similar results. Underwatering can cause the same symptoms as underwatering such as yellowing leaves. To a certain extent, it’s impossible to underwater a plant if you water it at least once a week.
On the other hand, most plants will survive just fine without watering at all! It’s very easy to overwater your hydrangeas. The best way to check is to stick your finger in the soil. If the soil is wet, don’t water yet.
4. Lack Of Humidity
This is a big problem if you live in a arid region or have extremely dry air in your home or office. The best way to increase the humidity around your plant is keep it out of drafts and away from any vents, A/C or heating sources. You can also use a humidifier or even a saucer of water on a humid day to increase the humidity around the plant.
5. Too Much Fertilizer
Most commercial fertilizers are way too high in nitrogen which will cause rapid vegetative growth at the expense of the flowers. Slow release pellets or organic fertilizers such as blood meal or bone meal are a better choice.
6. Excessive Heat or Cold
Your plant can’t survive if the temperature is either too hot or too cold. Most plants prefer temperatures between 45-75 degrees.
7. Insufficient Light
Your plant needs at least six hours of sunlight every day. If you don’t have a place in your home that meets these lighting requirements, you’ll either need to move the plant or your living arrangements.
8. Improper Pots & Other Containers
If your plant is growing in the wrong type of container or the wrong size pot, this can also cause problems such as poor drainage and increased susceptibility to fungal diseases. If you pot is too large, the soil will retain too much water and your plant will be susceptible to root rot. If it’s too small, the roots may become bound and girdled.
To prevent this from happening, transplant your plant into the correct size pot or container.
9. Improper Location
If your plant isn’t getting direct sunlight or doesn’t have the right temperature, it’s probably not going to thrive. This can usually be fixed by just moving the plant to a place that receives more sunlight or is warmer or cooler.
10. Fungal or Bacterial Infections
Most of these types of diseases are caused by stagnant water which then acts as a breeding ground for various types of harmful organisms. To prevent this from happening, you should use a pot with proper drainage or add some extra perforations. You should also be sure to water your plant and then discard the old water. Some breed of fungus or other disease can actually overwinter in your soil so it’s important to dispose of all the old water.
11. Animal or Human Consumption
While humans may find your Hydrangeas aesthetically pleasing, it is poisonous to most animals including your beloved family pets. Ingestion may cause excessive salivation, confusion, paralysis and even death.
If you have small children, it may be a good idea to keep the plant out of their reach and also put up a warning.
12. It’s A Sign Of Death
While some people may find this superstitious, there is some merit to this old wives tale. The Hydrangea does contain toxic and even deadly alkaloids such as hydrangeacin and norhydrangeacin. Humans may not even be able to detect the scent of these plants which is why they are sometimes used in flower arrangements. However, if your nose is sensitive enough you may notice a faint odor of rotten apples.
If you have small children or pets, it might be best to just avoid this plant altogether. Better safe than sorry. While you may think that your cat or dog wouldn’t be interested in eating a plant, many times they may be attracted to the scent and then develop a taste for it. They may also consume the Hydrangea by accident such as if it was in a vase that contained pet food or some other type of enticing substance.
13. Fluctuation in Temperature or Humidity
While it’s true that most plants thrive on a fluctuation in temperature and humidity, the Hydrangea actually does quite well in more stable conditions. It is not necessary to place this type of plant in a room with a fireplace or air-conditioner and it will also not benefit from being placed in a room that is either extremely hot or cold.
If you do find that your plant is suffering from extreme hot or cold conditions, there are a few steps that you can take. First, if the plant is too close to a heat source such as a furnace or radiator, move it further away. You can also place it in the sunnier parts of your home during the winter and out of direct sunlight during the summer.
Sources & references used in this article:
Temperature and photoperiod control of morphology and flowering time in two greenhouse grown Hydrangea macrophylla cultivars by CW Dunham – 1948 – University of Wisconsin–Madison
Hydrangea plant namedRavel by EF Nordli, M Strøm, S Torre – Scientia horticulturae, 2011 – Elsevier
Cloning and characterization of the antigenic membrane protein (Amp) gene and in situ detection of Amp from malformed flowers infected with Japanese hydrangea … by JR Sousa – US Patent App. 08/675,780, 1997 – Google Patents