Alliums are magnificent plants, therefore it’s worthwhile to save a few seeds to plant in the spring to increase the number for the garden.
It’s fascinating to grow cultivars and see what you get even though the seeds won’t be true to type. The seeds will sprout swiftly and mature into flowers in a few years. To obtain the finest show, when planting, pick a place that is protected, sunny, and has excellent drainage.
Try tapping the seeds directly into a paper bag if you want to keep the seedheads in the garden for winter interest. The cut seedheads could potentially be used again in indoor arrangements.
Are allium bulbs formed from the seeds?
The growing requirements for these relatives of common onions are the same whether you are growing alliums for their eye-catching, globular flowers, like the Star of Persia (Allium christophii or A. albopilosum), or for their flavorful, pungent bulbs, like leeks (A. ameloprasum) or chives (A. schoenoprasum). Depending on the variety, both types of alliums can be grown in USDA hardiness zones 3 to 11, producing edible bulbs or blossoms in the spring, summer, or fall before withering away in the winter and regrowing the following year.
How long does it take allium seeds to grow?
Alliums, which include onions, leeks, shallots, chives, and garlic, were once only considered to be vegetables, but today’s taller species with their enormous spherical flowerheads are among the most prominent members of the architectural plant community. Their stiff lollipop-shaped heads are ideal for counterbalancing tall, poker-shaped flowers, softer flowing grasses, and sharp vertical leaves, while their rich color—typically purple—looks stunning either in contrast to warm reds, yellows, and oranges or mixed with cooler tones of lilac, blue, and white.
Alliums can reach heights of up to 200 cm, with flowerheads ranging in size from small pompoms to enormous spheres of star-shaped blooms. For rock gardens at the front of the border, the little types work great. Garlic and chives grow well in these conditions, and they have the added benefit of confusing aphids and other bothersome insects so they go for food elsewhere. To ward against pests, surround other veggies and delicate plants like roses with these smelly plants.
Alliums are attractive not just when they are fully bloomed; the fallen flowerheads can also be left on the plant to dry and add architectural interest in the fall and winter. Hard frost will make the globes, especially those of Allium christophii, look gorgeous. For an eye-catching interior arrangement, you may also cut the flowers fresh and combine them with iris and thousand-flowered Gypsophilla.
Growing guide
Alliums prefer a warm, sunny location with healthy, rich soil. They can live in a more sandy area, but they will need to be well mulched if they want the truly magnificent huge heads. Since they are perennial bulbous plants, you can either plant them as potted plants year-round or as bulbs in the fall, putting them up to 15 cm deep. The plants will quickly take root and typically bloom the following year. Being bulbous also means that plants will eventually generate small offsets around the parent, forming large clumps.
Propagation
Any very big clumps can be separated into smaller portions in the late summer and replanted. Additionally, offset bulbils can be used to propagate new plants (newly formed, little bulbs). The majority of bulbils develop underground around the initial bulb. These can be carefully broken off and buried 1 cm deep in grittier compost. Aerial bulbils are produced by the Allium sphaerocephalon variation and emerge from the flowerhead. The same procedure as above can be used to plant these.
A content allium will freely self-seed. You can gather the seeds from the plant before they fall if you like to control where your new plants will sprout up (as opposed to leaving it up to chance and chaos). As soon as the heads (and stems) start to turn brown, remove them. Place in a paper bag so you can catch the seeds as the pods split open. The seeds can be kept in the bag in a cold location until the following spring, or they can be sown straight into the soil where you want them to grow. It can take up to a year for some alliums to germinate, so patience is essential.
Pest alert
Alliums are typically healthy plants, though during a humid spell they can develop white rot and downy mildew. Since they belong to the onion family, they occasionally experience onion fly attacks. Yellowing leaves are a typical early sign, and as white maggots eat away at the roots, the plant will suddenly collapse. Because the maggots are so deeply embedded in the soil and even in the bulb itself, this pest is very challenging to eradicate. To control onion fly, dig up any affected plants so that the maggots are not left to pupate, turn into adults and produce more grubs.
Variety guide
The most well-known flowering allium is undoubtedly A. giganteum, which grows up to 1.8m and produces 10-15cm-diameter spherical heads of purplish-pink flowers. Despite their size, almost never do they need to be staked. It looks lovely placed beside another monster, the grass Stipa gigantean, in the back of a border as a focus point. Another choice is the 80cm tall cultivar “Globemaster,” which grows best between shrubs in a sunny border and adds a dash of deep violet to the season with its enormous 15cm wide spherical flowerheads. Allium sphaerocephalon, which has stunning two-tone maroon and green flowerheads, may be the prettiest member of the clan. When combined with grasses or other globe-headed flowers like Echinops and Eryngium, it makes a stunning border plant.
The rich rosy-purple flowers of Allium hollandicum ‘Purple Sensation’ make it a charming addition to a sunny border. It will reach a height of 1 m. It looks especially beautiful when planted with fennel with feathery leaves. A. karataviense is ideal for the rock garden because it only grows to a height of 25 cm. Large, delicate pink blooms with unique leaves with dark crimson edges adorn the plant. Another option for a rock garden or for growing in a pot on the patio is the variety “Ivory Queen,” which is even shorter at 20cm tall and thrives in dry soil in a sunny location.
Crocus tip
Many of the taller alliums’ foliage will already be starting to die back by the time the blooms bloom, but if they are surrounded by perennials with appealing foliage (such herbaceous geraniums), these unkempt leaves can be covered.
Container plants
Alliums prefer a sunny location with well-drained soil, but if they are planted in pots, they must not be allowed to dry out in the spring as this can prevent the flower buds from opening.
Do bulbs or seeds produce allium plants?
No matter if they are beautiful or not, alliums can be multiplied through seed, bulbs, or division. As they normally don’t blossom for at least a year or two, if not more in some situations, starting from seed demands patience.
Also bear in mind that if a plant in your garden is a hybrid type, seeds you save from it could not grow true to the parent plant.
Provide well-draining, somewhat sandy soil for these lovely bloomers. If your yard is made of hard clay, add some sand to assist drainage because they don’t thrive there.
To find out whether you need to amend the soil, you could also wish to perform a soil test.
Flowering alliums only require well-draining soil, but you should make any necessary adjustments if your soil is substantially deficient in any of the three major nutrients: potassium (K), phosphorus (P), or nitrogen (N).
From Seed
You can buy seeds or use the ones you’ve saved from a prior growing season (more on that below).
After any chance of frost has passed in the spring, soften the soil where you want your plants to grow and scatter the seeds over it. Don’t bother properly spreading the seeds one at a time because they are little. Simply disseminate them widely over the growth area.
To avoid disturbing the seeds, cover them with 1/4 inch of dirt and water them thoroughly using your hose’s soaker attachment. Till the first green sprouts appear, keep the soil moist. After that, you can cut back on watering so that the top inch of soil can gradually dry out between applications.
Once the plants have emerged, thin them to the suggested spacing specified on the seed packet. The space required for different sizes of alliums vary.
By Division
Allium plant division is a fall task. It’s a good idea to divide your plants every three to four years to maintain their health and make sure they are evenly spaced.
At the end of the growth season, four to six weeks before the first frost, trimming back any remaining leaves and flower heads is the first step.
Allow a six-inch space around each plant as you excavate nine inches down. Although the roots of ornamental alliums are not particularly deep, you should try to minimize disturbance.
Remember that alliums can develop from rhizomes or bulbs, as was already indicated, but the procedure for digging them up and splitting them is the same for both.
Lift the soil mound with your shovel, then gently pry the bulbs or rhizomes out.
Put one of the bulbs back where it was growing after separating the others, at the same planting depth as before you dug it up. If you haven’t treated your plants in several years, mix a little bulb fertilizer with the soil.
Rhizomes can be divided by cutting them in half with a sharp knife. Reposition one of the rhizomes’ halves at the same depth where it was developing.
Plant the extra bulbs the same way you would new bulbs or transplants, which we discuss in the section after this one.
If you are unable to plant the bulbs immediately away, keep them in a cool, dark place for a few months. Rhizomes can be kept in the refrigerator for about a week in a plastic bag.
Planting Bulbs or Rhizomes
The procedure for planting bulbs is the same whether you purchase them from a neighborhood store, online, from a friend, or through division.
If you haven’t tested your soil, be important to do so before planting in the late summer to see if any supplements are needed.
Fork or shovel the ground in the fall, six to eight weeks before the first frost.
If desired, incorporate some bulb fertilizer, such as Jobe’s Organics Bulb Fertilizer, which is sold on Amazon.
How long does it take for allium seeds to bloom?
Scoop a soilless seeding mixture into a flat or tray for beginning seeds. Peat moss, vermiculite or perlite, sand, and occasionally a little amount of lime and compost are included in a soilless mix. Make sure the mixture is also sterilized for the greatest outcomes.
Allium seeds should be liberally scattered around the mixture’s surface in the tray or flat. For a more precise planting, you can use a pair of tweezers or forceps or pinch a group of seeds together between your thumb and index finger. The allium seeds should be placed 1/4 to 1/2 inch apart.
- The allium seeds should be spread out on paper towels to air dry for about a day.
- Peat moss, vermiculite or perlite, sand, and occasionally a little amount of lime and compost are included in a soilless mix.
Using a spoon or a tiny piece of wood, press the allium seeds into the seeding mixture approximately 1/8 of an inch deep.
Place the tray in a location that will stay at a temperature of about 70 degrees F for three weeks. At least once per day, check on the tray. Keep the allium seeds moist by spritzing the seeding mixture with a thin mist of water as needed rather than drowning them in water to the point where they become sodden and soaked.
After three weeks, move the tray and put it somewhere where the temperature won’t drop below 50 degrees or rise above 70 degrees. For the remainder of the germination period, keep the tray in this position. Germination can start in about a year, depending on the allium variety you are growing.
The majority of alliums produced from seed will start blooming in two to three years, according to the University of Maryland Fact Sheet on Alliums.
Can allium seeds be preserved?
Excellent bulb plants for perennial gardens are ornamental alliums. They are attractive onions, which come in a variety of species and cultivars.
Their sizes range from the smaller “Allium sphaerocephalon, a smaller allium, to Allium giganteum, a larger allium.
The majority of people grow alliums from bulbs since it is relatively simple to do so.
However, you can also start new plants from seeds if you are raising alliums that produce seeds. Increasing the number of allium plants in your garden is simple and affordable.
However, not all attractive allium plants will, and some will only produce a small amount.
A few varieties of allium are sterile and won’t set seed. In the case of cultivars like Allium “Globe Master” and Allium “Mount Everest,” this is true.
Some cultivars, like Allium, produce a lot of seeds “Allium christophii, also known as the Star of Persia, and Purple Sensation
The seeds from alliums that produce seeds can be kept, planted, and grow to produce more allium seedlings for the garden.
Is It Worth Growing Alliums From Seed?
Growing alliums from seed is absolutely worthwhile if you want to enhance your allium supply.
Remember that some allium bulbs, particularly the larger types, can be rather expensive.
Therefore, gathering some allium seed will ultimately save you money if you have a larger cultivar that produces seed and wish to grow your allium stock.
It’s crucial to understand that hybrids won’t be true to the parent plant, and that the new seedlings may have differences in size, form, and color.
Alliums: Should you deadhead them?
The blossoms of allium plants are large, softball-sized, and purple in color. They thrive in areas that are both sunny and protected, where the wind is less likely to tear the blossoms apart. They typically bloom in the early summer under these circumstances and last for three weeks on average.
Deadhead the blossoms once the flowers have gone. However, keep the foliage in place because it needs time to naturally wither in order for the bulbs to store energy for the growth of the following season. It’s a good idea to put alliums in a bed with later flowering flowers that might disguise and obscure them because the leaves may look a touch scraggly.
How are allium seed heads preserved?
I have an obsession with ornamental alliums. I keep growing more of them even though I now have around a dozen distinct varieties in my garden. Alliums are not only stunning to look at, but they are also long-blooming, pollinator-friendly, and appear to be immune to disease and pests, even deer.
And if that’s not enough, alliums’ seed heads are yet another reason to adore them. The seed heads of these late spring/early summer flowers can be an equally alluring lure after they have faded. They provide unique forms and textures to the yard and summer flower arrangements and many of them will survive for months. Continue reading to discover how to maximize the use of these eye-catching seed heads.
Use Allium Seed Heads in Fresh Arrangements
While they are still green, the seed heads can be clipped and added to bouquets of fresh flowers. Homegrown bouquets are given a distinct glitter by their color, shape, and texture. For this, Allium Purple Sensation works best.
Leave Seed Heads Right in the Garden
The seed heads can be left in the garden, where people will continue to be intrigued by their unique textures and shapes. The Globemaster and Gladiator alliums, which have sturdy, robust stems, are the ones that I find last the longest. Allium Christophiii’s seed heads, however, also persist for a long time. They may continue to look nice into August in a dry summer.
Paint the Dried Seed Heads
Another choice is to paint the seed heads once they have completely dried. Last year, I dried some Gladiator seed heads and used gold spray paint to embellish them. They emerged with a little bronzer appearance than gold. I might attempt silver paint this year.
The dried seed heads have also been painted glossy white and utilized as wedding decorations by me. The Gladiators are those displayed below.
Here’s a way for drying allium seed heads so you can paint them or just display them inside. When the seed heads are dry but before the seed capsules start to open and release the seeds, they should be painted or treated with a clear fixative. You can maintain the starburst effect and reduce the amount of seeds you need to sweep up by placing the seeds inside the capsules at the end of each “stem.”
The enlarged seed capsules are visible in the photo below, even though the seed head is not yet dry enough to paint.
Visit this post on Gardenista to see some lovely dried alliums (Allium schubertii) hanging from the rafters of an old stone barn in Wiltshire, England.
Mid- to late-fall is the ideal time to plant decorative alliums. Orders are accepted starting in May, and bulbs are shipped from early September through mid-November. The only way to guarantee you’ll get the variety you desire is to place your order early. Our entire collection is available to view HERE.