Shrub · Rosaceae
Grandiflora Rose
Rosa
Tall, long-stemmed, and happy to bloom from spring right to frost, the grandiflora hands you hybrid-tea flowers on a floribunda frame.
Full sun
Every 4–7 days
USDA 5–9
4–6 ft · 1.2–1.8 m
Overview
If you're new to roses, the grandiflora is a friendly place to start. It's one of the taller modern roses, bred in 1954 by crossing a hybrid tea with a floribunda, and from that pairing it inherited the shapely, high-centered flower of the hybrid tea along with the tall, clustered habit of the floribunda. That means one plant can give you cutting-quality blooms one to a stem or in full sprays. Queen Elizabeth kicked off the whole class and still holds a place in most gardens.
These are sun-loving shrubs that reach 4 to 6 feet and keep flowering from May all the way to frost. They do ask for a bit of steady attention, mostly regular water at the roots and one hard pruning each late winter, but the payoff is months of color. Give them room and good airflow and they stay noticeably healthier, and honestly, most of what goes wrong is easy to put right.
The one thing to respect is the thorns. Grandifloras carry sharp prickles along every cane, so a pair of gloves and long sleeves will save you a scratch at pruning time. Otherwise the plant is safe around pets and people, with no toxin to worry about, so you can grow it with an easy mind.
Care
The short version: give it full sun for at least six hours, slightly acidic and well-drained soil enriched with compost, a deep morning drink at the base, a monthly feed through the growing season, and one confident cutback in late winter.
Light
Give your grandiflora full sun, six hours or more each day, and it will bloom its heart out. It will put up with a little partial shade, but less light means fewer flowers and more disease, since the leaves stay damp longer.
Water
Water deeply and on a regular rhythm, ideally in the morning so the leaves have all day to dry. Soak the root zone instead of splashing the foliage, because wet leaves are exactly how black spot and mildew get their start. Aim for even, medium moisture every 4 to 7 days and you'll be right on track.
Soil
Plant into well-drained loam that's slightly acidic and rich in organic matter. A pH of 6.0 to 6.5 suits them nicely, so work in plenty of compost before planting and your rose will root deep and grow strong.
Temperature
Grandifloras are tougher than they look, handling anything from -20°F to 95°F (-29°C to 35°C) across their hardy range. They take real cold in stride once settled in, though a spell of extreme summer heat can tire the blooms.
Humidity
Ordinary outdoor humidity is all they need, so there's no number to fuss over here. Airflow matters much more, because still, damp air around crowded canes is just what the fungal diseases are waiting for.
Feeding
Feed monthly through spring and summer with a balanced rose fertilizer while the plant is actively growing. Ease off as the season winds down, and keep the nitrogen light, since it pushes the soft growth that aphids and mildew are drawn to.
Pruning
Prune with confidence in late winter to early spring, cutting the canes back to roughly 12 to 18 inches from the ground. Take out anything dead, weak, or crossing, then deadhead spent blooms through the season and fresh flowers keep coming.
Repotting
Grandifloras live in the ground rather than pots, so repotting hardly ever comes up. If yours is in a container, move it up a size when the roots circle round or poke through the drainage holes and blooming starts to slow.
Size & spacing
Expect a plant 4 to 6 feet (122 to 183 cm) tall and 2 to 3 feet (61 to 91 cm) wide. Give each one enough elbow room for air to move freely between the canes, and that alone is your best defense against leaf disease.
When to plant
Grandifloras follow the seasons, so timing is on your side. Set new plants out in early spring once hard frost has passed, or in fall where winters stay mild, then watch for that first happy flush of bloom in May and a steady stream of flowers right up until frost calls it a year.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: early spring after the threat of hard frost, or fall in mild climates
- Harvest: May to frost
Hardiness
USDA hardiness zones: 5–9
Temperature: down to -29°C
Troubleshooting
Almost every rose worry begins on the leaves and the soft new growth, and most of it comes back to wet foliage or crowding. The good news is that catching the early signs and responding quickly keeps a small thing from becoming a big one. Find what matches below, then step in while it still helps.
Dark spots creeping up from the lower leaves as they yellow and fall
Don't panic if you spot this. It's black spot, the most common rose fungus, and it almost always begins on the older leaves down low. Wet foliage is what lets it in, so switch to a gentle morning soak at the base, pick off the marked leaves as you find them, and tidy away anything that drops. A little pruning to let air and light through, plus a fungicide, and your plant bounces right back.
Fix:
- Remove and dispose of infected leaves and fallen debris
- Water at the base in the morning and keep foliage dry
- Improve air circulation by proper spacing and pruning
- Apply a labeled fungicide preventively if disease pressure is high
A dusty white film on the fresh growth with young leaves curling
This one looks worse than it is. That pale, dusty coating is powdery mildew, and it tends to show up when the days are warm but the nights turn cool and humid. Snip away the most affected shoots, open the plant up to more sun and fresh air, and go easy on nitrogen so you're not feeding the soft growth it loves. If it hangs on, a labeled fungicide or horticultural oil will see it off, and your rose will be just fine.
Fix:
- Prune out heavily infected shoots
- Improve air circulation and sun exposure
- Avoid excess nitrogen that pushes soft growth
- Apply a labeled fungicide or horticultural oil when needed
Little soft insects gathering on the buds and leaving a sticky coat
Take heart, this is one of the easiest problems to handle. Those tiny, soft bugs clustered on the tender shoots are aphids, and the sticky honeydew they leave can go black with sooty mold. A firm blast of water knocks most of them off, and insecticidal soap or horticultural oil clears any stragglers. Better still, lady beetles and lacewings will happily do the job for you, so keep the nitrogen low and let those helpers move in.
Fix:
- Dislodge aphids with a strong spray of water
- Apply insecticidal soap or horticultural oil to affected growth
- Encourage natural predators such as lady beetles and lacewings
Toxicity
Here's a reassuring bit: true roses are non-toxic to pets and people alike, so a curious nibble from a cat, dog, or rabbit won't cause poisoning. The petals and hips are actually edible. The only real hazard is mechanical, those sharp thorns along the canes, so just handle the plant with a little care.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
You can relax about your cat here, since the ASPCA counts true roses as non-toxic and a nibbled petal or leaf won't poison them. The thorns are all you really need to mind, as a sharp prickle can catch a curious paw or mouth.
Dogs None
Your dog is perfectly safe around a rose, and a mouthful of foliage causes no poisoning at all. Just keep half an eye out for thorn scratches on the nose or paws.
Horses None
Rest easy about horses too, as the ASPCA lists roses as non-toxic to them. A grazing horse can browse the leaves without any harm, though the prickly canes might tug at the lips.
Rabbits None
Rabbits can safely enjoy rose leaves and petals, and plenty of gardeners offer them as a little treat. Just strip the thorns off any cuttings before you hand them over.
Livestock None
Goats, sheep, and cattle can browse rose foliage with no risk of poisoning at all. The only thing to watch is the sharp prickles running along the canes.
Birds None
Birds have nothing to fear from a rose, and the hips even make a welcome bit of winter food for many wild species.
People None
Rose petals and hips are edible and find their way into teas, jams, and syrups, so no worries there. The thorns are the one hazard, so slip on gloves whenever you prune.
Most grandiflora roses bear sharp thorns (prickles) on the canes that can cause scratches and puncture wounds; the hazard is mechanical, not chemical. Wear gloves and long sleeves when pruning or handling.
Varieties
Only a handful of grandifloras show up in most gardens, and these are the ones well worth getting to know by name.
Queen Elizabeth
As the very first grandiflora ever offered, this upright grower reaches 4 to 6 feet and gives you double silver-pink blooms both one to a stem and in long-stemmed clusters.
Gold Medal
A tall grandiflora much loved for its golden-yellow, hybrid-tea-shaped flowers that ride on long stems just right for cutting.
Tournament of Roses
A vigorous, easygoing grandiflora with good disease tolerance that unfurls coral-pink double blooms in generous clusters.
Companions
Grandifloras do best beside aromatic plants that confuse pests and share their love of sun and good drainage, and worst anywhere near a black walnut.
Plant near
garlic: Aromatic alliums interplanted near roses are a traditional companion thought to help deter aphids.
lavender: Drought-tolerant, sun-loving companion that shares full-sun, well-drained conditions and attracts pollinators without crowding roots.
Keep apart
black walnut: Black walnut releases juglone, which can harm many garden plants; keep roses away from its root zone.
How to propagate
Roses can be multiplied in a few different ways, though some ask a good deal more skill than others. Here's how each method works and what you can expect.
GraftingDemanding
Late summer for budding onto rootstock · One growing season
This is the method nurseries rely on to keep named grandifloras true to type, budding a scion onto a hardier, disease-resistant wild rose rootstock in late summer. The young plant finds its feet across a single growing season. It does call for a practiced hand, so it's absolutely fine to leave this one to the professionals.
Stem cuttingsModerate
Late spring through summer from semi-hardwood growth · Several weeks to a few months to root
You can take cuttings from healthy, current-season stems any time from late spring through summer, once the growth has firmed up into semi-hardwood. Give it patience, since rooting can take a few weeks to a few months and how readily it happens depends on the cultivar. Do remember that patented varieties can't be legally propagated.
LayeringModerate
Spring to summer while canes are flexible · One season for roots to form
This is a lovely gentle way to make a new plant. While the canes are still supple in spring or summer, bend a low one down and tuck a section under the soil. Over a season, roots form where the buried wood meets moist ground, and then you can snip the new plant free and move it wherever you like.
Myths
Roses are poisonous to cats and dogs.
You can set this worry aside, because the ASPCA lists true roses in the genus Rosa as non-toxic to cats, dogs, and horses, so a chewed leaf or petal won't poison a pet. A scratch from the thorns is the only real risk. Just be careful with unrelated plants that borrow the rose name, like desert rose or Lenten rose, since those really can be toxic.
Grandiflora is a botanical species of rose.
It's an easy thing to assume, but grandiflora is a garden class, not a species. Breeders created it back in 1954 by crossing hybrid teas with floribundas, marrying the lovely hybrid-tea bloom to the tall, clustered habit of a floribunda.