It has been some amazing weather the past couple of weeks! The weather has felt very much like June weather with temperatures in the high 60’s and low 70’s during the day. The warm temperatures are giving those of us who do not work outside, pause. Many have called asking how to best take care of their plants. Given the number of calls received, I felt this would be a great topic to discuss.
Because the temperatures are so warm and the ground is not covered in snow and ice, this is an excellent time to cut back perennials and clean up debris in your garden. All of your ornamental grasses will thank you by putting on their best show if you cut them back to about two inches above ground level. The one exception that I am aware of is Blue Oat Grass. This grass does not really like a good “haircut”. It is best to rake out, or pull out by hand, the dead foliage to clean it up.
Care of roses and hydrangeas becomes a bit more complicated. Pruning techniques are based on knowing the variety of rose and hydrangea you have in your garden. This is the reason why. For rose varieties, there are shrub roses, Rugosa roses, floribundas, teas, climbing, groundcover, landscape, etc., etc., etc. Hydrangeas are not as plentiful, but equally as confusing. These are the oak leaf, mopheads (macrophyllas), paniculatas, arborescens (Annabelles), and lacecaps. I will go over the basics of rose and hydrangea care separately.
Basics of rose care are as follows (from Texas A&M AgriLife Extension):
Here are some basic practices of pruning roses correctly in all gardens, regardless of type: 1) remove any canes that have been damaged by insects, diseases or storms; 2) remove one of two canes which may be rubbing one another; or 3) remove canes that are spindly or smaller in diameter than the size of a pencil. After pruning, according to these general recommendations, cut hybrid teas, shrub roses, florabundas, and grandifloras back to about 12 inches for large flowers.
Climbing roses and rugosas generally are pruned to renew plant vigor by removing the old canes since the most productive and finest blooms on are produced on canes that arise from the bottom of the plant the previous year. These newer canes produce more desirable growth and flowers. Prune canes back so they are maintained in the desirable shape and area.
When making cuts on the ends of branches, cut at 45 degree angles above an outside bud one-half inch above the bud with the lowest point on the side opposite the bud, but not below the bud itself. When removing branches, never leave stubs since these die and can cause problems on the plant later. Always remove branches by cutting to a lateral branch or bud, or back to the base of the rose plant.
Basic hydrangea care is as follows (from All About Hydrangeas):
1) Mophead hydrangeas (blue and pink varieties) do not have to be pruned back – ever – unless they are very old. Removing dead stems is the only pruning that must be done for the health of the plant, and these can be removed at any time. Dead blooms can also be removed at any time.
2) All dead stems should be removed from hydrangeas every year.
3) After the plants are at least 5 years old, about 1/3 of the older (living) stems can be removed down to the ground each summer. This will revitalize the plant.
4) In addition, if it becomes necessary to prune a plant to reduce its size, it may be cut back in June or July without harming the next year’s bloom.
This method is used for the arborescens (Annabelle types). These hydrangeas bloom on new stems. These hydrangeas bloom every single year, no matter how they are treated. The only time they cannot be pruned is in the spring when they are preparing to bloom. Because the blooms are so large, they may require staking to hold up the beautiful blooms.
Paniculatas (PG/Limelight types) can be pruned in the fall, winter, or spring to clean up the dead flowers and any crossing branches or stems. It is not necessary to prune them every year.
Paniculata hydrangeas are the only hydrangeas that can be pruned into a tree-form. If you are growing a paniculata as a tree, the developing trunk and main top branches should not be removed. If a tree form paniculata is cut or broken off close to the ground, it will grow back as a shrub unless the training and pruning is started again from the new shoots.
This is a great time to put down a slow release fertilizer, not a liquid fertilizer. Any fertilizer will push new growth. This may be a bit harmful to your plants given that we should be having temperatures no higher than 40 at this time of year. Who knows how long these warm temperatures will remain! We may get hit with a really cold snap which will impact any new growth that has not been hardened off. Slow release fertilizers are released at specific, warmer temperatures. They also provide nutrients to the plant gradually, over time.
This is a great time to divide your perennials or move trees and shrubs. Plants are still dormant and they will not be stressed by extremely warm temperatures. This will allow your plants to establish themselves in your garden during the entire growing season rather than only part of the season.
This information is only very basic. You may find additional information by searching various websites or by calling us at Caan Floral and Greenhouses.