When & Where To Plant Allium Bulbs? [By Zone]

With its long green base top by rotund purple or whitened blooms , allium , or flowering onion , is a striking improver to any garden . Interestingly enough , it ’s also part of the plant genus that include garlic , Allium cepa , leek , shallots , schnittlaugh , and others .

If you ’re interested in develop this beautiful industrial plant , you may wonder , " When and where should I plant allium bulbs ? " Well , you ’re in the correct shoes !

When and where to set genus Allium bulbs depends on the zone in which you live . You should implant them in autumn when the soil has cool down off after the summertime .

Here ’s when to set for each geographical zone :

In the sleep of this article , we ’ll apportion more detailed information about when and where to plant alliums . That includes dirt pH level , sun penury , and more . You probably have more genus Allium question , too , and we ’ll do our best to answer those as well .

So , rent ’s get started !

When & Where To Plant Allium Bulbs? [By Zone]

Because they need metre to develop their root over the winter before blooming in late spring , you should engraft genus Allium bulb in autumn . And , since they need cool temperature to help them acquire correctly , you should plant them after the ground has cooled .

Of naturally , this timing vary depending on where you are locate . In general , though , you could follow this schedule :

What Kind of Soil Do Allium Bulbs Like?

The most important thing to consider when choosing soil for your genus Allium is making sure that it ’s well - drained . Since genus Allium are bulbs , they are at high jeopardy of waste in damp ground .

Try work gumption or grit into the planting area if your soil is dense and filled with clay . You ’ll also want to choose an rising situation that does n’t collect rain .

away from drain considerations , Allium are very tolerant of almost any type of grunge . However , when given an choice , they prefer grime with a neutral to slightly acidic pH of 5.5 to 6.5 .


If you ’re timid of your soil ’s pH level , you’re able to easily check with an at - house psychometric test kit . Luster Leaf makes a kit that includes 10 tryout strips .

dawn here to view it on Amazon .

How Much Sun Do Alliums Like?

Alliums will grow happily in partial nuance to full sunlight . However , planting them in a spot with full sun maximizes their fairly myopic growing time of year .

Receiving more sun also helps them grow stronger root word . If you want to void ending up with drooping flowers , select a cheery smudge for your genus Allium .

How To Plant Allium Bulbs

Planting allium bulbs is moderately well-situated , but we ’ll take the air you through the process since there are a few details you ’ll need to be aware of for the best outcome .

What You’ll Need

Pick A Spot

First , choose a spot to embed your genus Allium using the light and territory demand note above . Additionally , alliums come in various top , ranging from 5 " to 4 ' tall , with most clock in around 2 ' .

Because of this , you ’ll require to consider the plants grow near your alliums and ensure that the taller plants are grow behind , the short ones .

Prepare The Hole

Next , use your digger to toil a gob . The size of it of the hole reckon on the size of the genus Allium bulb . A good rule is to plant the electric-light bulb about 2 to 3 time deep than its elevation .

For example , if your bulb is 3 " long , you ’ll need to dig a 6 " to 9 " deep trap . you may utilise a taping measure or yardstick to measure the medulla oblongata and the depth of the hole , or you may plainly eye it .

After figuring out the hole ’s depth , dig it wide enough for the bulb to fit snugly . The breadth of the hole does n’t matter as much as the depth .


If you ’re planting more than one allium bulb , space the holes 4 " to 8 " aside . Again , this depends on the size of your chosen genus Allium mixed bag . you could figure out the spatial arrangement by finding out how big the flower foreland will be , then add together 1 " or 2 " .

Since Allium grow straight up instead of disperse , they typically bet better when imbed as snug together as potential .

Plant The Bulbs

constitute the allium bulb by placing it in the hole with the pointy remnant face up . Then , fill again the hollow with crap and compact it gently around the bulb .

After you ’ve planted all the bulbs , give them a generous soak with water from the lachrymation can or hose . This helps the soil settle around them and gives your bulbs a heavy start as they start get !

How To Care For Alliums

Alliums are an easy - to - like - for plant , but you’re able to do a few thing to ensure they stay healthy and have a productive spring up season .

Here are some supplies you might want to like for your alliums throughout their arise season :

Water Sufficiently

As they originate , you should aim to give your alliums about 1 " of weewee weekly . This means that you ’ll need to water whenever the top inch of soil dry out out .

However , be mindful of over - watering . Since alliums are lightbulb , it ’s easy for them to set forth rotting if they get too damp .

Use Stakes If Necessary

If you have one of the very tall allium varieties that reach height of 3 ' or 4 ' , you may want to stake them . Keep an middle on the Allium as they grow , and if they start drooping or fall over , you’re able to give them some support with a stake .

To back an allium , find a interest that is just slightly shorter than your works . you’re able to purchase wooden or metal stake or just use a tenuous but unattackable stick from a tree in your yard .

tug the stake about 4 " into the territory next to the allium , or however deep it needs to go to be inviolable .

Now , take a slice of string between 12 " and 24 " long and twine it gently around the allium and stakes .

It should be close-fitting enough to bear the plant ’s stem close to the post but not so tight that it cuts into the stem . Tie the end of the drawing string together to hold everything in place .

Add Fertilizer

There are two times during your genus Allium ’s growing time of year that you should apply plant food . One is immediately after the shoots look , and the other is when the plants start to bloom . Use 5 - 10 - 10 fertiliser on the shoot and 0 - 0 - 10 or 0 - 0 - 50 fertilizer as they bloom .

In increase to these two time during the growing time of year , add 5 - 10 - 10 or all - aim bloom plant food in the spring of every yr . If you ’d rather not use fertilizer , you could get similar results from adding aged manure or compost to the grunge .

To watch more about plant food , you’re able to correspond out our article " How Long Does Fertilizer Last In Soil ? "

Watch Out For Diseases

Alliums are moderately resistant to disease , but like other bulbs , they ’re at risk formildewandrust . Inspect your allium ’s leaves every week to terminate trouble before they get serious .

Mildew usually shows up as powdery snowy on the tops of the leaves or sometimes on the stems . Rust , on the other helping hand , is cerise - chocolate-brown spot that eventually turn into pustule .

Remove Faded Blooms and Foliage

Keep an eye on your allium as early summer glide path , and the blooms pop out to fade . When this happens , cut the prime head off and use them in fresh flower arrangements .

They also dry out extremely well , which can provide you with coloured bloom all class round !

After cut off the flowers , admit the folio to produce for a few more weeks . This gives the genus Allium meter to continuephotosynthesizingand saving muscularity in the bulb for the long winter months .

Around the heart of summertime , you ’ll notice your allium ’s leaves and halt protrude to move around lily-livered and shrivel . you could remove all of the foliation by lightly draw it out of the ground .

It should easily come off from the bulb with a gentle tug . If there ’s any resistance , impart it alone and try again in a few more twenty-four hours .

After the foliage has all been remove , your genus Allium is in a dormant United States Department of State and will remain that way until next spring .

In Closing

Allium bulbs should be planted in the descent . you’re able to grow them in zona 3 - 5 from late September to October . In zones 6 - 8 , on the other hand , you should wait until October to mid - November .

Plant the electric-light bulb in well - drained , neutral to slightly acidulous soil , and choose a spot that gets partial wraith to full sun for the best result .

If you ’re interested in growing other case of medulla , you might also like our clause " How To raise Tulip Bulbs . "