For The Union-Tribune
The spring garden is a place of delight. Lush green leaves, productive new canes, fresh blooms and emerging rose buds are each an uplifting cause of celebration. When we look, we also encounter blind shoots and basal breaks in the spring garden. They both start with the letter ‘B’, but the similarity stops there because our response to each and the desirability of each is a study in vivid contrast. Blind shoots are undesirable and make us feel crestfallen and robbed of joy. Basal breaks are hugely desirable and make us feel jubilation.
What is a blind shoot?
A blind shoot is a disheartening absence of buds at the top of stems. You will see short stems that fail to produce a flower, either because the plant failed to produce a bud altogether or the bud aborted development after it had started. Of course, a stem that terminates without a bud means there will be no future bloom. Don’t waste your time waiting to see if a bud will grow from that stem. A blind shoot is a road to nowhere. There will be no bloom.
Why do blind shoots occur?
Blind shoots are not an uncommon occurrence. Experts surmise that light and climate factors may be implicated. Some experienced rosarians suspect that the bush is sending out more stems that it can with blooms.
Temperature and light are two of the factors that influence the rate of photosynthesis. The plant converts sunlight to produce food in its leaves and exports the sugars to other parts of the plant for growth. Very hot and cold temperatures can decrease the plant’s ability to photosynthesize. In late winter and early spring, lower levels of light can also limit the rate of photosynthesis, and sharp fluctuations in temperature can slow and stop tip growth. Roses develop blind shoots with these conditions because the plant directs its energy to essential growing parts of the plant. Plant vegetative growth wins over bloom production.
Are some classes of roses more susceptible?
A walk through my garden revealed that the blind shoots I spotted were mostly on several varieties of hybrid tea roses.
What to do about blind shoots
Maximize light: There are many days in late winter and early spring with overcast skies. Roses, and especially hybrid tea roses, must be planted in the sunniest locations in our garden and spaced appropriately so they are not shaded by other roses and plants.
Nip out the blind shoot: Don’t just ignore blind shoots. When the blind shoots are growing in the center of the bush, remove the stem altogether to open the center of the bush to light and air circulation which will help minimize disease. If the blind shoot is vigorous and growing toward the outside of the bush, you can prune back just the blind tip. This will allow the rose to try again to set a bud.
What is a basal break?
Our roses put energy into rejuvenating themselves by putting out basal breaks. A basal break is the emergence of a new cane that originates from the base of a grafted or own root rose bush. On a grafted rose, it sprouts from the bud union. The excitement over basal breaks is because new canes are more productive with blooms than old canes. And new canes replace old canes and continue the vigor of the plant.
Basal breaks in the rose garden are a rosarian’s delight. Our former past president, the late Bob Martin, wrote that the basal break “should be viewed as a new child added to the family.” An exciting addition indeed!
A basal break usually starts out reddish in color. We must always be on the lookout for it, treasure it and protect it as it is very tender and vulnerable to being broken. Stake it and be careful not to snag it when moving a hose through the rose garden.
Basal breaks can go unnoticed, shaded and hampered in their growth by less desirable canes or growth in the center of the bush. Make way for them! Prune out any old less desirable canes and unnecessary growth that may be obstructing their path to allow this vital new growth the space, sunlight and air circulation it needs. Strong new stems growing not from the bud union but emanating from existing canes must also be cherished and protected.
Don’t confuse a basal break growth with a sucker, which is growth emerging from the rootstock of a grafted rose. A sucker must be removed. If you are unsure if the growth is coming from the bud union, wait until you can determine if the foliage and growth habit resemble the named variety of your plant. In California, the root stock is usually climbing Dr. Huey, which grows very fast and has a burgundy-red bloom. In removing a sucker, twist or wrench it off below the soil level to prevent it from regrowing.
Is there anything we can do to encourage basal breaks?
The mechanisms that prompt basal breaks are not fully understood. Some roses are more generous than others in the production of basal breaks. We most often see this new growth in the spring at the beginning of the growth cycle. ‘Secret’ is one of my favorite roses because this renewal of growth is one of her very lovely characteristics.
Give them space to grow: When we prune our roses in the winter we remove dead, damaged or very old canes. We should saw the canes out at the bud union and not leave stumps. This opens up space at the bud union and encourages and stimulates the opportunity for new basal breaks.
Apply alfalfa (2-0-1): Alfafa contains triacontanol, a natural growth stimulant that can contribute to plant vigor and bloom production. It can be applied to the soil as a meal, pellets or as a tea. It is reputed to contribute to basal breaks although I cannot attest to this as I have not seen basal breaks on all my roses, and I have applied alfalfa to each one of them.
Epsom salts for basal breaks is an old wives’ tale
There is a longstanding belief among many rosarians that the addition of epsom salts (magnesium sulfate) promotes new basal breaks. Researchers have found no benefit to this practice in controlled and replicated trials. Adding epsom salts when the soil is not deficient in magnesium can be problematic: If too much of one nutrient accumulates, it can prevent other necessary nutrients from becoming available to the plant.
We grow roses for their blooms, that third and all-important ‘B’ word in the rose garden. Blind shoots and basal breaks stand in vivid contrast to each other. They are on opposite ends of the bloom production spectrum. When we are vigilant and respond to each of them, we maximize the directive stated by the Reverend S. Reynolds Hole in his 1869 “A Book About Roses,” when he declared “There should be beds of roses, banks of roses, bowers of roses, hedges of roses, edgings of roses, baskets of roses, vistas and alleys of roses.”
Perwich is a member of the San Diego Rose Society, a Consulting Rosarian and a Master Gardener with UC Cooperative Extension. For more information, visit rose-harmony.com.
San Diego Rose Society Rose Show and Auction
The San Diego Rose Society will host its 97th annual Rose Show from 1 to 5 p.m. on May 3, and from 10 a.m. to 3:30 p.m. on May 4 at the Ronald Reagan Center, 195 E. Douglas Ave, El Cajon. A Rose Auction will be held at 2:30 p.m. on May 4. For more information on these free events, visit sandiegorosesociety.com.
