For many years now, I have been growing various vegetables as a hobby in my spare time, which is what ultimately led me to studying horticulture. I find it fascinating to watch as plants grow from seed to fruit and to then finally be able to make use of the literal fruits of my labour. Favourite fruit: Strawberries and cherries Favourite vegetable: Potatoes, tomatoes and garlic
Alfalfa is mainly cultivated for green manure and as feed, especially for horses. It is valued for its high protein content and impressive dry matter yields.
Alfalfa (Medicago spec.) plays an important role in feed production. Continuously flowering and rich in nectar, it is also an important food source for wild bees. Read on to learn everything about alfalfa cultivation and uses.
Alfalfa, also known as lucerne, is a perennial forage crop that has been cultivated for centuries as an important source of feed for livestock such as cattle, horses, and sheep. But how tall does an alfalfa plant actually grow? In this complete guide, we will explore the growth habits and height potential of the alfalfa plant.
An Overview of Alfalfa
Alfalfa is a member of the pea family and has a deep taproot system that allows it to be quite drought tolerant once established. The stems of alfalfa plants grow erect and can reach heights of up to 1 meter (3 feet) tall when mature. Alfalfa grows best in full sun and in deep, fertile, well-drained soils with a neutral pH between 6.5-7.5.
The leaves of alfalfa are compound, meaning each leaf is actually made up of three leaflets. The flowers are purple in color and alfalfa plants will bloom from spring until fall when growth is terminated by freezing temperatures. Alfalfa is highly nutritious, containing significant levels of protein, fiber, vitamins, and minerals.
Factors That Influence Alfalfa Height
There are several key factors that influence how tall an alfalfa plant will grow:
Climate and Geography
Alfalfa growth is strongly influenced by climate, latitude, and geography Alfalfa grown in cooler climates and at more northern latitudes will typically grow taller before reaching maturity compared to alfalfa grown in warmer southern regions. This is because cooler temperatures slow development and prolong the vegetative growth phase
Soil Fertility
The fertility and nutrient levels of the soil also impact alfalfa height. Plants grown in highly fertile soils with optimum levels of nitrogen phosphorus and potassium will be able to sustain a more extensive period of vegetative growth and reach greater heights compared to alfalfa grown in nutrient deficient soils.
Cutting Schedule
The cutting schedule used for alfalfa also influences its height. Taking earlier cuttings allows for more regrowth cycles per season. With more frequent cuttings, plants have less time to reach their maximum heights compared to when cuttings are less frequent.
Cultivar Selection
There are many different alfalfa cultivars and some have an inherently more upright, tall growing habit than others. Selecting cultivars described as “tall”, “erect”, or “upright” types will result in greater height potential.
Plant Population
Higher plant populations lead to competition between plants for sunlight, nutrients and water. This competition stresses plants and can result in shorter heights. Lower plant populations reduce competition and allow more extensive vegetative growth and taller plant heights.
Irrigation
Adequate and timely irrigation ensures alfalfa plants are never under drought stress. Maintaining optimum soil moisture allows for continuous plant growth and maximum height potential. Significant drought stress will result in slower growth and reduced heights.
Typical Alfalfa Heights
Now let’s take a closer look at typical heights an alfalfa stand can reach:
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At early vegetative growth when plants are still establishing, expect heights of 6-12 inches.
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During the later vegetative stage just prior to bud formation, plants will reach 16-24 inches in height.
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At 10% bloom when flowers have formed on the lower parts of the plant, expect heights of 20-36 inches.
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At full flower when flowering has reached the top of the plant, maximum heights of 24-40 inches are common.
These heights assume moderately fertile soils, adequate moisture, and plant populations of around 6-8 plants per square foot. The tallest portions of an alfalfa stand are often found along the edges where competition is less. Heights in the interior of dense stands may be shorter.
Best Height for Harvesting
To produce high quality hay or silage, alfalfa is often harvested before full maturity. Research has shown the best compromise between yield, quality, and plant health occurs when alfalfa is cut at around 10% bloom and heights of 25-30 inches.
Cutting at later maturity stages results in lower forage quality and energy content. Taking earlier cuttings at vegetative stages produces excellent quality but significantly reduces yields. Aim for that “Goldilocks zone” of 25-30 inch heights for ideal harvest timing.
Adjusting Cutting Height to Optimize Growth
Being mindful of alfalfa’s growth habits allows you to tailor your harvest schedules and cutting heights to achieve your forage production goals:
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Take early cuttings at vegetative stage when rapid regrowth is desired.
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Cut at 10% bloom and 25-30 inches when aiming for maximum yields and quality.
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Harvest at 50% bloom and 30-36 inches if optimizing late season yield is priority.
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Lower cutting height to 6 inches when thinning or removing diseased stems.
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Raise cutting height to 12 inches when plants are stressed or winters are harsh.
By observing your alfalfa heights and adjusting cutting schedules, you can maintain plant productivity and health over many years of production.
Final Thoughts
In ideal growing conditions, alfalfa can reach heights of 3 feet or more at full maturity. But to balance yield, quality, and plant health, target harvest at around 10% bloom when alfalfa reaches heights of 25-30 inches. Adjust cutting schedules and height as needed based on your goals and conditions. With this complete overview on alfalfa height, you now have a better understanding of what to expect from this productive and versatile forage crop.
Growing alfalfa in the garden
Alfalfa prefers a warm and sunny location with chalky, well-drained, nutrient-rich soil. Deep loam or loess soils are suitable soil types. Avoid acidic compacted soils prone to waterlogging. Alfalfa plants grow best in soil with a pH value of 6.5 to 7.5. With its extensive root system, alfalfa copes better with a lack of water rather than too much, so soils should be dry to moderately moist. That being said, the crop has a high demand for water, so it is important the soil has good water storage capacity.
The sowing period for alfalfa is long, ranging from April to mid-August. If sown in spring, lucerne plants can develop enough to be ready to survive winter on their own. If starting your alfalfa seeds outside, check the soil temperature; the seeds need a soil temperature of at least 5 °C in order to germinate.
To prepare the soil for sowing alfalfa seeds, loosen it deeply and remove all weeds. Then sow the seeds to a depth of 1 to 1.5cm and press down lightly on the soil. We suggest using 25 to 30g of seeds per 10m². For large areas, simply spread the seeds over the soil’s surface, and then gently work the seeds into the substrate with a rake. Use the back of the rake to lightly press the soil down. Do not forget to water the seeds after planting them; from seeds to seedlings, keep the soil evenly moist. The first alfalfa seedlings should appear after about a week or two.
Tip: did you know that alfalfa can also be cultivated indoors on a windowsill or in the kitchen? Alfalfa sprouts are healthy and a refreshing way to refine dishes even in winter.
You want to know who’s behind Plantura?
For many years now, I have been growing various vegetables as a hobby in my spare time, which is what ultimately led me to studying horticulture. I find it fascinating to watch as plants grow from seed to fruit and to then finally be able to make use of the literal fruits of my labour. Favourite fruit: Strawberries and cherries Favourite vegetable: Potatoes, tomatoes and garlic
Alfalfa is mainly cultivated for green manure and as feed, especially for horses. It is valued for its high protein content and impressive dry matter yields.
Alfalfa (Medicago spec.) plays an important role in feed production. Continuously flowering and rich in nectar, it is also an important food source for wild bees. Read on to learn everything about alfalfa cultivation and uses.
Alfalfa Seeding Year Considerations
FAQ
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