Many of us receive poinsettias (Euphorbia pulcherrima) for the Christmas season and hydrangeas (Hydrangea macrophylla) for the Easter season. What do you need to know about these plants and how can you help them survive if you plan to use these plants in the landscape around your home? Here is some information I know you will find useful.
When I was young man (a long time ago) Christmas was not Christmas without the beautiful color of poinsettias donning the entryways of our friends and neighbors homes. People either bought poinsettias and placed them around the home for holiday color or gave them away as gifts to their friends. Back then we only had one variety, the red bract poinsettias. After a few weeks these bracts would fall off and eventually we would throw the plant away. Well now poinsettias come in a multitude of colors and leaf shapes and many of us would like to plant these specimen plants in our gardens.
Most of the new poinsettias you purchase come with a bright red, gold, or green foil covering the pot. This makes the plant look very pretty and colorful. Remove the foil. Place the pot on a dish to catch the water that seeps through the plant when you water. Many people leave the foil covering the plant and then they water. The foil holds the water around the base of the plant and the plant begins to wilt. Soon afterwards the plant begins to drop its leaves and then dies. Foil wrappings are probably one of the worst culprits to poinsettia death. The other problem is that some people do not know when to water because they can not see that the soil has dried out and the plant wilts then dies. By removing the foil and testing the soil for moisture regularly, you are on your way to keeping your plant alive through the holidays and then ready for the garden.
Well the Holidays have passed and you are ready to plant your poinsettia outside. Go outside and find a sunny place in the garden to plant your poinsettia. Once you have found this place do not plant your poinsettia. Wait until nighttime and go back to the spot you picked out. Look around for light from a streetlight or an exterior light that is shining on the spot you picked out. If there is light in that spot find another spot that is free from nightlight. If you plant a poinsettia in a place that gets light at night your poinsettia will not be able to set bracts. In the nursery, poinsettias are shaded to promote the bract color change. Pick a spot that is sunny during the day but that does not get any indirect or direct light during the night and your plant will grow well and give you the holiday color you want.
Go ahead and plant your poinsettia in the spot you have chosen and be sure not to plant too deep. Be sure to water in well and add a little fertilizer. Remember if we get some cold weather (a freeze) your poinsettia could be injured so make sure you protect your plant if necessary. During the growing season prune back your plant at least twice (June and August) to promote a thick head. Be sure not to prune more than one third at any one time and no more pruning after mid August!
Hydrangeas are wonderful additions to the landscape and many are just starting to come into bloom around Easter. Most of the hydrangeas purchased during the Easter holidays are the blue or pink variety however; there is a white variety (Hydrangea arborescens) which has been bred to bloom now during the Christmas holiday. I have seen several of the white hydrangeas available at local garden centers and just like the poinsettias we talked about earlier, they come with the same foil wraps. You must remove this foil and place the pot on a saucer to catch excess water. These white hydrangeas are just like the mop-head varieties (blue/pink). Once the threat of frost or freezes has been eliminated, it will be time to place these plants in the garden. You can place these new white varieties right next to you common pink/blue varieties you have now. Most hydrangeas are grown in a semi-shade environment so find a place in the garden that gets full afternoon shade. Morning sun is ok but hydrangeas will prefer to be well shaded in the afternoon. If placed in full sun they will likely be burned.
The pink and blue varieties of hydrangeas will switch colors depending on the pH of your soil. Hydrangeas planted in soils which are low in pH (i.e. soil pH of 5.0 to 5.5) will give the plants blue flowers. Soils with higher pH will usually return hydrangeas with pink flowers even if the flowers you had in the past were blue. Use an acid forming fertilizers such as azalea/camellia fertilizers. These types of fertilizers help to lower the pH of the soil and will help the plant maintain the blue flowers you love. Remember, because of the buffering ability of soils, your soils pH will return to the higher pH if your plants are left alone. I have heard of people using aluminum sulfate to help lower the soil pH but this can be risky and can cause damage to the root system if you use too much. I prefer you use pelletized sulfur to lower the pH. You can get this product at most nursery garden centers. Note: White hydrangeas will not turn a different color no matter what you do.
Hydrangeas in central Florida(pink and blue) normally bloom in the May-June time frame. Do not despair if your plants are killed to the ground during a freeze. Once established, hydrangeas will come back from the base the following spring. Most plants will grow to a height of 3 feet in this area but you must be vigilant to inspect your plants for insects such as scales, mites, aphids, and powdery mildew. For insect problems use a product like Talstar (active ingredient is bifenthrin) or if you have powdery mildew you can use Dithane M-45.
Hope this news helps you and your plants! Have a Merry Christmas and a Happy New Year! Remember without plants, we wouldn’t be here!