The Sun Valley Red Maple is a compact form of the red maple, which is ideal for smaller gardens, or where a full-sized tree would be too large. It grows more slowly, and it matures between 20 and 35 feet tall, rather than the normal tree, which is over 40 feet tall. Its upright branches mean it also has a narrower spread, so it can be planted in more restricted spaces. It may be smaller, but its fall colors are just as powerful, ranging from brilliant orange-reds to darker burgundy-reds. It is an ideal choice for a smaller lawn, or anywhere a smaller tree is needed in restricted spaces.
- Strong orange-red and darker red fall colors
- Neat oval crown, with smaller leaves
- Excellent compact tree for smaller gardens
- Good cold-tolerance for northern areas
- Grows well in both ordinary and wet soils
Full sun will bring out the full intensity of the fall colors of the Sun Valley Red Maple, but it also grows in partial shade. It grows in a wide range of soils, including wet ones, so low-lying places, and damp ground are good planting areas. It even tolerates periodic flooding, yet it grows just as well in urban soils, and it is moderately drought tolerant too. Pests and diseases are rarely problems, and no trimming is needed to keep its neat form.
Shade trees are a vital part of all but the smallest gardens, but there is often the danger they will outgrow their space and become a problem. If you have more limited space in your garden, or in the specific part of it where you want to plant a tree, you obviously need to be more careful about the size of the tree you plant, and to choose wisely. Often, we find it hard to judge the space that is available, and the ultimate size of the tree we are planting, meaning many trees are planted which simply don’t have enough room to mature. In the near-future this can involve expensive tree work, or the removal of a tree decades away from the natural end of its life, which is always a great loss. If you want to grow a beautiful shade tree in limited space, then it makes sense to choose one that is smaller, which could mean a smaller species of tree, or, as with the Sun Valley Red Maple, a smaller variety of what is usually a popular larger tree.
Growing Sun Valley Red Maple
While ordinary red maple trees grow to be between 40 and 50 feet tall, with a spread of 30 or 40 feet, the Sun Valley Red Maple is smaller, growing to between 20 and 35 feet in height, and from 15 to 25 feet wide. The branches are more upright, making an attractive oval crown, with a neat and dense structure. This significantly smaller size makes all the difference in fitting this tree onto a small lawn, or as the central element in a courtyard. It can be planted closer to buildings, and it won’t cast such a long shadow in spring and fall, letting more light into windows. Planted as a boundary on your property, you can leave more room for the rest of the garden, or you can plant a row in a narrower space. Almost half the size of other forms, this compact tree allows you to have the beauty of red maple, especially in fall, without needing so much room. As well, it is slower-growing, adding only around 12 inches a year, so it stays small and compact for longer, and takes longer to reach its final size.
The leaves of the Sun Valley Red Maple are also smaller, keeping it neat, and in proportion to its more compact size. They are usually 3 inches long, and no more than 4 inches long, with 3, 5 or sometimes 7 deeply-cut lobes, and irregular serrations around the leaf edge. The upper surface of the leaf is bright green and fresh, with a smooth, glossy surface. The lower side is lighter green. In fall the leaves reliably turn all the brilliant shades we expect from a red maple, ranging from glowing orange-red to deeper reds, and a tree in full color is a glorious sight. In spring, before the leaves emerge, you will see dark red fat ‘buds’ along the branches, which are the pollen flowers. These are tiny, and have no petals, but they add an interesting touch in early spring. Their arrival tells us that the first new leaves will be here soon, in their fragile light greens, heralding another season. This is a male tree, so it cannot produce those annoying maple seeds, so the litter is considerably reduced. This is another benefit of this tree in smaller spaces, where litter can be a bigger problem.
Grow the Sun Valley Red Maple in full sun for the best colors. This tree grows best in cooler parts of the country, and it will not color well in areas above zone 7. We recommend the Brandywine Red Maple for southern areas, as this tree has excellent heat tolerance, and develops rich colors even in hotter zones. The Sun Valley Red Maple is however very cold resistant, and perfectly hardy – with superb fall colors – in zone 4. It grows best in moist soils, and it thrives even in wet soils and areas that are sometimes flooded. It also grows well in regular soil, and this even tree tolerates urban conditions. It does prefer acidic or neutral soils, and it is not recommended for highly alkaline soils. Once established it is moderately drought tolerant, particularly in cooler zones. Young trees benefit from some supplementary watering during longer dry spells. Pests and diseases are normally never problems. No trimming is needed, but if you do want to prune or trim your tree, do this in summer, as it will bleed sap if cut in late winter or spring.
History and Origins of Sun Valley Red Maple
The red maple, called Acer rubrum, grows in forests, swamps and along rivers all the way from eastern Canada through the east and southeast, and into Florida. It also grows westward into Texas and the edges of the Plain states. The variety called ‘Sun Valley’ was developed as part of a breeding program carried out by the National Arboretum in Washington, D.C. Scientists there have developed many of our best garden plants, and they try to create new forms of popular plants that satisfy specific regional needs. None of their work is patented or trademarked for profit. They crossed two existing varieties of red maple, called ‘Red Sunset’ and ‘Autumn Flame’, and tested the seedlings from that cross, looking for improved forms. They selected ‘Sun Valley’ for its excellent color, smaller leaves, compact growth and smaller ultimate size.