Hybrid Tea - Any of a group of roses with high-centered buds in the form of La France, Crimson Glory, Peace, Pascali, Bewitched, Touch of Class, or Garden Party. Hybrid Teas are decended from Tea roses, usually being crosses between Tea Roses and some other European Old Rose - Gallica, Damask, Bourbon, etc. Many of the best early Hybrid Teas were very sturdy, very beautiful, and very fragrant. As they were inbred generation after generation to develop novel colorations and accentuate certain features, it was common for weaknesses to crop up and for fragrance to drop out of the picture. Breeding programs over the last decade or two have begun to bridge these gaps and repair the damage.
Large-Flowered - Roses that bear a single well-formed flower at the end of a long cane, typically a Hybrid Tea. In these pages Large-Flowered is not used where it should be, but the term more familiar to Americans, Hybrid Tea is. Again, I ask the keepers of rose language to forgive me for perpetuating confusion.
Mildew - One of two fungal diseases that afflict roses. Powdery mildew that creates a powdery white coating on the leaves. Downy mildew creates black spots on the leaves. Both can be treated or prevented with fungicidal sprays.
Number 1 -Roses grown on grafted root-stock and sold bare-root are graded by size. The larger ones are graded Number 1. Those somewhat smaller are graded Number 1 1/2. And the smallest ones are graded Number 2. The details of the specification can be found at ASTM.
Recently, I have seen roses graded Jumbo, but I don't know if this is peculiar to one grower. A rose is a plant that you buy to keep for decades, and the best really don't cost that much. It is conventional wisdom that the lower-graded ones never really do catch up with the higher graded ones, so why save a pittance buying inferior stock?
Hips - A fruiting body of a rose plant, though not all roses produce them. Left on the plant, they will turn color, usually red or orange, which can be a distinct attraction during the winter. The hips do cause the rose plant to stop blooming, so deadheading remontant roses can improve later crops of flowers. Rose hips are one of nature's most concentrated sources of vitamin C. They are dried and used in herbal teas and made into syrups and jellys.
Hybrid - An individual that results from cross-breeding of two species. Ideally a hybrid will inherit the favorable traits of both parents. Sometimes there seems to be some kind of synergy that occurs and the resulting individual has special qualities not found in either parent. Usually, a hybrid will have some of the weaknesses of its parents. Sometimes, too, weaknesses will be found that occur in neither parent.
Hybrid Musk - Any of a group of highly foliferous and highly remontant roses, most of which were bred by Pemberton and his distributor Bentall, and most of which are decended from Trier. Many hybrid musks strongly fragrant, but the most popular ones are so on account of their generosity with flowers , their freely branching habit and their extreme vigor. There can be a kind of concinity between the flowers and the foliage that makes these roses almost always seem much more beautiful than could be explained by the beauty of any of the individual parts.
Hybrid Perpetual - They are more remontant than Bourbons and Portlands, but the plants are upright instead of being shrubby. The best flowers run the gamut from the highly ordered old rose blossoms of Baronne Prevost in rose and the nicely quartered blossoms of Baronness Rothschild in pale pink to the buff colored high-centered Hybrid Tea style of Marchioness of Londonderry and Frau Karl Druschki. In style this group really runs the gamut from old rose to modern rose.
Hybrid Rugosa - Any of a group of rose plants closely decended from one of the Rugosa species. The best retain many of the Rugosa qualities such as cold hardiness and disease resistance, wrinkled leaves, fragrant & informal flowers, rounded shrubby habits, and vigorous production of rose hips.