The best time to plant bare roots is during the winter months. However, unlike the mainland, our temperatures are still quite warm and you should be careful not to let the bare roots dry out. When they are received, soak the complete bare root, canes included, in water for 1-2 days. Some rosarians add a Vitamin B product like Super-Thrive to the water. Others rinse their bare roots in a light bleach solution to kill bacteria.
I plant my bare roots in containers then transplant them to the
ground after they've made a nice root ball. The containers range in size from 2 gallons to 7 gallons, depending on the root size. An advantage to using containers is that you can keep
the bare roots in the shade, protecting them from drying out in the sun. Then when the plants leaf out, you can gradually move them into the sun.
I use Super Soil mixed w/compost, 1/3 cup of osmocote, several
handfuls of a heavy, fine-grained, gravel, and perlite. Perlite increases drainage while the gravel helps to keep the pot from being blown over by the wind. Tom Mui uses 50% perlite
because he grows roses permanently in containers and perlite does not decompose providing good drainage. Others, Nii Nursery for example, use cinders to provide drainage. Unlike perlite
and vermiculite, cinders are pretty heavy and can help keep the pot upright on windy days.
Herman Davey, one of our members and an expert rosarian, recommends "Gardener & Bloome Rose Planting Mix", available from C Brewer.
At the bottom of the pot, you can a 1/2 cup of superphosphate or bone meal. Herman also mentions adding a handful of blood meal and green sand. Before planting the bare root, trim off any broken roots or dead growth on the canes, or spindly canes. To help prevent the canes
from drying out, you can try a product like Anti-Wilt, which will coat them with liquid plastic polymers to prevent moisture from evaporating.
If you plant your bare roots directly in the soil, make sure that
you keep them moist. Whether in the soil or container, plant the bare root so that the bud union is above the ground. It makes it easier to spot suckers (shoots from the rootstock) and to prune
dead wood off of bud unions. When digging a hole in the ground, rosarians suggest a 2'x 2'x 2' size hole for your bare root or plant.
Growing Roses in Containers
In Hawaii, there are many places where the soil is not
amenable to gardening. Land used formerly as sugar cane fields has shown significant levels of manganese toxicity. The University of Hawaii has an article on this subject :
Managing Manganese Toxicity in Former Sugarcane Soils on Oahu. Also, volcanic,
sandy or salty soils can be quite inhospitable to plants. Containers provide a viable alternative. In fact, many rosarians are very successful growing their roses exclusively in containers. I've read that hybrid teas should be kept in 15 gallon containers and minis in 5 gallon containers, but have seen many get by with 10 gallon and 3 gallon containers. I suggest starting your plants in smaller containers and then transplant them to bigger ones as they grow. They seem to grow faster this way.
The American Rose Society has some excellent articles on keeping roses in containers on the
ARS website. You may also want to grow your roses on your lanai. In that case, the UH article, Enhancing your Lanai, Balcony, or Patio with Container Plants , is perfect for your needs.
Because of our heat, watering your roses is essential. Rosarians
typically recommend giving rose bushes 5-7 gallons per week. This will vary depending on your soil type, bush size, and the rainfall in your area. Sandy soils require more water than clay soils, and as expected, the bigger the bush, the more water it needs. In Hawaii, rose plants need to be watered at least every other day and I must admit to watering mine every day,
except for when it rains. I've heard people worry about overwatering their in ground roses,
but have rarely seen it happen, and only in cases where rose bushes are actually standing in a pool of water for long periods of time. On the other hand, I've seen lots of roses that don't get enough water. They grow to be undersized bushes producing small leaves and fewer blooms.
If you live in a really rainy area with poor drainage, you might consider growing your roses in containers. If your bushes are getting too much water, usually the bottom leaves of the plant will wilt (in spite of all that water), yellow and fall off.
Container roses can suffer if watered too much and the drainage is inadequate. Rooted cuttings like ones offered by some vendors can also be sensitive to overwatering, so be careful with them. If the soil in a container has a sour smell, it has inadequate drainage. If a cutting dies from the bottom up, it probably has been overwatered.
Many HRS members water their roses using a timed drip system. This is invaluable for people who are busy or go on trips. You have to be careful though, that the water is not just going to a small area. In CA, we used to have a drip system, giving us the freedom to travel, but gave up on one in Hawaii after a few months. The drip emitters kept popping out and I had to keep adjusting them. So for the past 7 years, I've been using a water wand, dragging the hose behind me as I go and my bushes look better than they did with the drip system.
For articles on watering, see the American Rose Society's
webpage on watering on their website.