Asters need full sun, and slightly acidic, loamy soil. This perennial grows best when given 8 hours of direct sunlight each day. Some varieties of this beautiful plant will tolerate part shade, but the results will not be as good. If your asters receive at least 6 hours of full sun a day, this should be sufficient for strong, attractive flowers. If less than 6 hours of direct sun is available, you are risking smaller flowers, fewer flowers, or even flowers that wilt and die, depending on how sun-deprived they are. For best results, give your asters a full day of direct sunlight.
How Many Hours of Sun Do Asters Need?
Asters require 8 hours of full sun daily, but they may survive with few ill effects if they are exposed to at least 6 hours of direct sunlight each day. If you plant your asters where they receive fewer than 6 hours of full sun per day, chances are, you’ll be disappointed with the results.
- Asters need 8 hours of full sun each day.
- In many cases, 6 hours of direct sunlight is sufficient.
- Fewer than 6 hours of full sun can affect the health and appearance of your asters.
Depending on how much sunlight they are deprived of, asters may not grow as healthy or tall, and may not bloom as brilliantly as asters grown in the sun. The best way to avoid these problems is to aim for at least 6 hours of direct sunlight each day. However, a full day of direct sunlight will provide the ideal environment for asters.
Can Asters Grow in Indirect Sunlight?
Asters usually won’t die when they are grown in indirect sunlight. In fact, when they are grown from seeds, it’s best to allow them to break the ground before exposing them to full sun. However, once they begin to grow, at least some full sun each day is important. If sun-deprived, your asters may grow leggy and develop too much foliage.
- Asters can grow in indirect sunlight during certain periods of their life cycle.
- When planting from seeds, it’s good to start asters out in indirect sun.
- Once your asters begin growing, full sun is important for continued health.
Sometimes, asters may bloom almost as beautifully in indirect light as asters grown in full sun. However, if temperatures are cool or the soil becomes too moist due to no direct sunlight, the results may be unsatisfactory. Root rot may occur if the soil is allowed to remain overly moist in indirect light. Alternatively, if you grow your asters in indirect light, you may end up with smaller than average flowers or flower buds that are slow to open.
Can Asters Grow in Shade?
Asters can grow in shade, but the results are not usually satisfactory. Wood asters are a type of aster that can tolerate partial shade, but even this variety should not be grown in full shade.
- Asters can live in shade, but they will not grow up healthy.
- Wood asters can tolerate part shade, but full shade is not recommended even for this variety.
- Asters grown in full shade may never reach full maturity.
- If the buds do open, their color may not be as brilliant, and the petals may die prematurely.
If grown in full shade, asters may never reach their full height, and in some cases, they may fail to bloom at all. Other times, when flowers open the color is lackluster. However, the biggest risk of growing asters in the shade is that your plants may die prematurely.
What Happens if Asters Don’t Get Enough Sun?
If asters receive too little sun, you can expect fewer blooms. When too little full sun is available, asters have a tendency to grow floppy and leggy. This happens as they crawl outward in search of sunlight. Shade-grown asters are often abnormally small, with a lot of leafy foliage and few, small flowers.
- Aster blooms will not flourish normally if they receive too little sun.
- Aster plants may also become leggy and floppy if sun-deprived.
- Too much foliage and abnormally small buds are common signs your asters aren’t getting enough sun.
- Asters may grow at odd angles to try to find sunlight.
Asters may grow at awkward angles in an effort to find sunlight, which may eventually lead to drooping or broken stems. To avoid these problems, make sure you plant them where they can get full, direct sun throughout most of the day.
Can Asters Get Too Much Sun?
Asters can get too much sun in some cases. Although they are sun-loving flowers overall, sun-scorch is possible, depending on the average climate where you live. Midday sun may be too hot for certain varieties of asters, as evidenced by wilting, drooping, or yellowing of the stems, leaves, or petals.
- Asters can get too much sun.
- Wilting, drooping, or yellow spots on the plants are signs of sun-scorch.
- If your asters seem stressed from the sun, provide afternoon shade.
If you live in a cooler climate, a full day of sun is imperative to the health of your perennial asters. The best way to determine if they’re getting too much sun is to evaluate them during the hottest part of the day. If they appear to be stressed from the heat or sun, provide afternoon shade to revive them. A row cover or shade sail on a frame over your asters can help provide much-needed shade.
How Much Sun Do Asters Require?
Asters grow best when given sun all day, although certain varieties of this lovely flower tolerate part shade. When growing asters in your garden, remember these tips:
- A minimum of 6 hours of direct sunlight daily is usually adequate for asters, but 8 is better.
- Less than 6 hours of full sun may result in fewer flowers or smaller buds.
- Asters may die if they are deprived of adequate sunlight.
- If they aren’t receiving enough light, asters grow smaller, with fewer flowers and poor color.
- If your asters are wilting or are forming yellow spots in hot temperatures, they may be suffering from sun scorch. Provide some shade so they can recover.
- When starting asters from seeds, provide indirect light until they sprout.
- Once new asters have sprouted, gradually move them to direct sunlight for 6–8 hours daily.
Asters grow well in moist, well-drained soils in sunny garden beds. In climates with hot summers, make sure they receive morning sun, but consider planting them in an area that is partially shaded in the afternoon. In regions with mild summers, provide your asters with all-day sunlight.