Harvesting allium seeds, which is similar to harvesting the majority of other flower seeds in the garden, is the first step in saving the seeds.
The secret is to let the seeds develop on the plant and then harvest them when they are completely dry.
Collecting Allium Seeds
In late spring to early summer, alliums blossom. Tulip time coincides with the appearance of our Purple Sensation allium blossoms.
Each allium’s flower head is composed of countless tiny star-shaped blossoms that, if fertilized, will develop into numerous small seed pods on the dried flower head.
The foliage dies back once the flowers have stopped flowering, and the seed heads start to dry.
The allium plants in the garden take on a completely new structural appearance thanks to the withered flower heads and sprays of seed pods.
They are still very interesting even in their dried state, and because they are so unusual, many gardeners leave them in the garden even at this point.
Allium seed heads can be harvested much sooner than many other types of garden seeds, which are typically harvested in the fall, if you intend to collect allium seeds.
Before gathering ripe seeds, watch for the seed pods on the seed head to turn brown and dry.
Mid- to late-summer is when the allium seed heads in our garden are dry and ready to be harvested.
When seed pods open and release their contents, the seeds themselves will naturally disperse if not collected and fall into the garden.
To Collect Allium Seeds From Seed Heads
- There are numerous ways to gather allium seeds.
- You can either tap the seeds into a bag or container and leave the seed heads in the garden, or you can collect the complete seed head together with the seeds.
- Collect the seeds on a dry day when they are not wet from heavy dew or rain.
- When cutting an allium seed head, keep the bag or container underneath it because the seeds might be quite loose and easily fall onto the garden.
- Cut the seed head beneath, then carefully insert it in the bag or container.
- During this procedure, a lot of seeds will probably fall into your container.
- If required, label the container, especially if you are collecting different kinds of seeds.
- Mark the type of seed and the date of harvest on the bag if you’re using one to collect the seed heads.
- Before stratification, keep seeds in a cool location.
What Do Allium Seeds Look Like?
Allium seeds are small and oblong, and their color has returned. The surface of the seeds is rough, with numerous tiny puckers and dents.
The allium seeds look a little like the actual allium bloom to the unaided eye, and they do.
Are seeds available from allium flowers?
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, yet during a humid time they might get white rot and downy mildew. Since they belong to the onion family, they may experience onion fly attacks. Yellowing leaves are a typical early sign, and as white maggots eat away at the roots, the plant will abruptly collapse. Because the maggots are so deeply embedded in the soil and even in the bulb itself, this pest is particularly challenging to eradicate. Dig up any afflicted plants to get rid of onion flies so that the maggots can’t develop into adults, pupate, and create 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.
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.
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.
Are allium seed heads salvagable?
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.
How should allium heads be handled after flowering?
Post-bloom maintenance for alliums is quite simple. Simply continue to water the plants sparingly until they start to shrivel and turn yellow. At this point, you have the option of either dividing the plants or cutting them all the way to the ground.
Divide allium bulbs every three to four years. Simply use a shovel to dig around the plant and lift the bulbs out. You should see a group of bulbs that you may gently separate with your hands. Replant a few in the same location, and immediately transplant the others to different sites.
It’s considerably simpler to take care of allium bulbs that you don’t wish to divide. When the foliage starts to fade, simply trim it back, and in the fall, mulch the soil with 2 to 3 inches (5-7.5 cm) of material. In the spring, remove the mulch to allow room for fresh growth.
Alliums: Should you deadhead them?
Alliums are drought-tolerant, thus it’s typically not essential to water plants that are rooted in the ground. Summer irrigation is not preferred by plants since it could lead to bulb rot. Alliums planted in containers will require routine watering, but watch out for soggy compost.
Overwintering
Winter cold can be more damaging to plants in pots. to ensure their winter survival
- Place containers in a protected area.
- Place them in the lee of a wall, within a cold frame, or a greenhouse to provide them with some protection from the winter rain.