It is hard to believe that it almost the end of July. Where has summer gone? And where has the rain gone. The parched lawns and gardens are in great need of rain. It is difficult to keep your own watering regiment going for weeks at a time. Nevertheless it is important to remember to water newly planted trees and shrubs throughout their first growing season. Efficient watering is done on a weekly basis by using a soaker hose or a hose that will be giving a slow steady flow of water for at least an hour. Timely rainfall would be ideal but I sure wouldn’t rely on this for sufficient moisture, and especially not this summer.
The end of July is also a time to stop fertilizing rose bushes. Perennials also do not need fertilizing that stimulates foliage growth. Plants are beginning to slow down and get ready for dormancy and the natural process of directed energy to root growth. A slow release 5-10-5 fertilizer or organic soil amendments are ideal to encourage healthy roots in preparation for winter survival. It is okay to continue to use a weekly dose of liquid fertilizer on any annuals you have planted which will help encourage flowering into fall.
A perennial that will soon be in bloom is the aster. Asters look like small daisies, but they bloom in many colors. They are a very versatile plant as they grow in varying heights and thus can be planted at the front, middle, or back of the flower garden. The bloom period can last a number of weeks which makes this an excellent plant for the late summer or fall garden.
Asters prefer moist well drained soil and lots of sunshine. Some asters need more space to allow for their expanding size as they mature. This also helps provide good air circulation to help prevent disease. Leafhoppers can pose a problem by transmitting a disease called aster yellows. The plant will show signs of this by displaying distorted growth or malformed flowers. As mentioned in the last article, this disease is incurable and the plant would need to be destroyed. Japanese beetles also like asters, but usually these beetles can be handpicked from your plant as they feed in the day and are quite visible.
There are many aster cultivars. Some will be more aggressive and will send out underground stems or stolens. Others will grow tall and lanky or short and bushy. It is important to check the plant identification tag to be sure you are buying a plant that meets your specific garden needs.
Asters will begin to form buds as the days get shorter. It is important not to have them exposed to extended periods of night light as this can delay the bloom time or in some cases cause your plant not to bloom at all. Blooms can be increased by pinching back the plant early in the season. This encourages side- branching which results in a bushier plant with more flowers. Pinching is not recommended on the taller varieties as it will result in a smaller flower size.
Asters do not do well in drought conditions, so it is necessary to water your plants to encourage bloom. Hopefully Mother Nature will provide us with some much needed rainfall in the coming weeks.
Until next time…happy gardening.
Nina Binkley, UW Extension Master Gardener volunteer