Q. I planted three yellow Lady Banks roses on my south
wall when I moved here 10 years ago. Two years ago, my neighbor planted a white,
lady Banks rose nearby. This year I noticed white roses growing on my “yellow” Lady
Banks rose. I thought these flowers might be from their plant but traced it back
to the base of my vine. Will my yellow roses eventually all be transformed to
white? How do you explain this botanically?
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| Some lady banks roses are grafted onto route stocks that produce white flowers. Is this a miracle when white flowers appear? |
A. I wish we could declare it a miracle, submit it
somewhere and have a party. But, unfortunately, it probably isn’t. What makes
this observation even more interesting is that Lady Banks rose comes in two
basic colors; yellow and white flowering selections.
somewhere and have a party. But, unfortunately, it probably isn’t. What makes
this observation even more interesting is that Lady Banks rose comes in two
basic colors; yellow and white flowering selections.
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| White Lady Banks rose |
On rare occasions, a totally different plant can grow
from a mother plant. This is called a “sport” in horticultural terms. These are
genetic abnormalities, a mutant if you will. Most mutants are not valuable,
wasted time in evolution, but sometimes they can be valuable.
from a mother plant. This is called a “sport” in horticultural terms. These are
genetic abnormalities, a mutant if you will. Most mutants are not valuable,
wasted time in evolution, but sometimes they can be valuable.
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| Yellow Lady Banks rose |
One example is the nectarine. The fruit from a nectarine tree
is basically a hairless peach. The tree is identical to a peach tree. If this
hairless fruit had hair on it, we would call it a peach.
is basically a hairless peach. The tree is identical to a peach tree. If this
hairless fruit had hair on it, we would call it a peach.
The first nectarine, ever, was found by a farmer growing
as a “sport” from a peach tree. Mutants like these can give rise to totally new
types of plants which can become important commercially. If it wasn’t for this observant
farmer, we wouldn’t have nectarines today.
as a “sport” from a peach tree. Mutants like these can give rise to totally new
types of plants which can become important commercially. If it wasn’t for this observant
farmer, we wouldn’t have nectarines today.
Back to your situation.
Then how did these white flowers
suddenly appear on a totally “yellow” plant? Unfortunately, the explanation is
probably quite simple and not very “miraculous”.
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| Notice that this sucker with white flowers on it is coming low on the plant, close to the rootstock. |
Lady Banks rose is grown commercially by grafting the
Lady Banks part, called the scion, onto a different rose plant used for its
roots; the rootstock. This rootstock is a totally different kind of rose flower
but it’s roots that have desirable characteristics that can contribute to the
survival of the scion plant.
Lady Banks part, called the scion, onto a different rose plant used for its
roots; the rootstock. This rootstock is a totally different kind of rose flower
but it’s roots that have desirable characteristics that can contribute to the
survival of the scion plant.
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| Lady Banks rose over the top of the wall |
In your particular case, the scion, the yellow Lady Banks
rose, was probably grafted to Rosa
fortuniana, a white rose commonly used for it’s very desirable traits as a
rootstock.
rose, was probably grafted to Rosa
fortuniana, a white rose commonly used for it’s very desirable traits as a
rootstock.
Rosa fortuniana
shows excellent resistance to nematodes and a great deal of tolerance to poor
soils. It is a very common rootstock used for roses planted in southern
climates of the United States.
shows excellent resistance to nematodes and a great deal of tolerance to poor
soils. It is a very common rootstock used for roses planted in southern
climates of the United States.
These white flowers come from a “sucker”
growing from this white “rootstock” rose. As it gets older, this sucker produces
white flowers, quite a bit larger than flowers of the yellow Lady Banks, but an
excellent rose in its own right just the same.
growing from this white “rootstock” rose. As it gets older, this sucker produces
white flowers, quite a bit larger than flowers of the yellow Lady Banks, but an
excellent rose in its own right just the same.
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| Yellow lady banks rose used as a screen on a trellis behind some retail establishments. |
You can elect to prune these “white suckers”
from the mother plant and keep it totally yellow or let these suckers grow and
have a beautiful combination of white and yellow flowers on the same plant.
Some pruning may be required to achieve a balance in growth between the two
roses so that one does not dominate over the other.
from the mother plant and keep it totally yellow or let these suckers grow and
have a beautiful combination of white and yellow flowers on the same plant.
Some pruning may be required to achieve a balance in growth between the two
roses so that one does not dominate over the other.