by Elizabeth Spence
End of summer: it’s that time of year when the bulb catalogues are on a mission to get us to buy and plant our spring flowering bulbs before it’s too late. This is nothing new. Here are some from 1891, 1898 and 1916.
In these old catalogues, the pictures inside are black and white. Modern catalogues, as we know, have mouth-watering pictures of daffodils, tulips, snowdrops, grape hyacinths and so many more.
Our hearts start beating a little bit faster, our blood starts rushing, the temptation increases, and we know we don’t really have room for more bulbs. So what are we going to do?
Easy! Grow them in containers!
They can make stunning focal points on the deck, by the door, or even placed in the flower bed to fill a gap. They can be moved to any other spot as and when the whim takes us. They’re perfect for those who don’t have a yard as well.
POTS AND CONTAINERS
- In our climate, it’s probably best to use thin plastic pots or things that can withstand the temperature fluctuations in winter, and then insert them into your decorative frost-sensitive containers in the spring.
- Terra-cotta pots look lovely, for instance, but should only be used decoratively to contain the pot with the bulbs in. Unless you go to great lengths to protect them, they are likely to crack over the winter, so better to be safe than sorry.
- The smallest diameter for a pot is probably about 12”. Twenty-inch or more would be amazingly dramatic! Even bigger – even more dramatic!!
- The smallest height of a pot would be about 12” as well.
- General rule for choosing pots: the bigger the better. The more volume, the more protection in winter.
- There are endless choices when it comes to decorative containers: bathtubs, old boots, a toilet, kettles, tin cans, sinks, chairs with the seats taken out, wheelbarrows, jeans, tree stumps, garbage cans or anything vaguely hollow you just happen to have lying around. But that’s for the spring.
PLANTING UP
Pots and Soil
Bulbs are very prone to rot, so the first thing to do is to make absolutely sure there is good drainage: there must be holes in the bottom of the pot. The more the merrier.
There is a huge controversy in the gardening world at the moment about whether you should use pieces of broken pot, a layer of gravel, grit, crushed aluminum cans, golf balls, or small stones or anything like that at the bottom of the pot to aid in drainage.
The argument against using anything at all is concerned with the “perched water table.” If you want to find out more about this, have a look here.
I’m not going to get into the argument, except to suggest that you put a piece of paper towel or coffee filter over the holes to stop the soil washing out and to stop earwigs and ants getting in. Being very old-fashioned, I would also put one or two pieces of old pot crock over the central hole in the bottom. But that’s just me.
General purpose potting mix is ideal for bulbs in pots. You don’t need any fertilizer. After all, the whole point of a bulb is to store enough food to allow it to flower once.
Single layer Planting
- The first thing to do is put a good layer of soil in the pot – minimum of about three to four inches
- Bulbs can be planted much more closely in a pot than they would be in the garden. You can place them right next to each other but without touching. Remember, the pointy side is always up.
- The standard recommendation for planting bulbs is that they be covered by 3-4 times their own height in soil, but you can play around with this to some extent in a container. Here is a general chart:
Many people just plant one type of bulb together – all daffodils or all tulips for instance – using the same colour or mixing the colours. In fact, it is recommended by some that you should only plant one type of bulb in one container, not mix them. I’m not sure why.
Here are examples of tulips and daffodils planted on their own.
In Canada you can get bulb kits, but they only contain one type of bulb, as far as I know.
In the UK, Suttons Seeds sell pre-planted spring bulb trays which do away with the job of choosing what bulbs to use. The trays are made of degradable paper.
If anyone knows if these are available in Canada, please let us know!
Here are some of Suttons pre-planted combinations to inspire us:
Lasagna Planting
Single species or varieties in one pot can certainly be quite stunning, as can different varieties all planted at the same depth.
But now we come to the layering method called “lasagna planting” which has become popular over the last few years.
You don’t put in just one layer of bulbs, or mixture of bulbs, you plant two, three or four layers at different depths – generally the biggest at the bottom and the smallest at the top, all divided by a layer of potting mix.
This is in fact what happens in nature – different bulbs align themselves at different depths in the soil.
The benefit of this way of doing things is that you get a lot more blooms in a given space.
So here we have our layered planting. This is our “bulb lasagna!”
Some things to consider are:
- The eventual height of the flowers: if they all flower at the same time for instance, you don’t want tall ones on the outside of the arrangement blocking out smaller ones on the inside. So you plant the tall bulbs in the middle and the smaller ones higher up around the outside.
- The size of the leaves: some tulips and alliums can have big leaves which may hide the other flowers.
With the lasagna method there are lots of opportunities for experiment!
- You can use different varieties of one type – rock garden, mini, medium and tall daffodils, for instance, all planted at the appropriate depths and positions.
- You can plan to have everything flowering at the same time,
- You can choose ones that bloom at different times for a longer flowering season.
- You can think about the combinations of flower colours and leaf shapes.
- You can play around with the positioning and density of the plantings.
Here are some examples
And here is a useful chart from Brecks that shows when the various bulbs flower
AFTER PLANTING
Watering
The first thing to do once everything is planted up is to water the pot. There is a lot of conflicting information on how much water to give initially, and whether you should water at all during the winter.
Michael Ashton of Ashton’s Garden Centre in Tatamagouche has a 90% success rate of storing potted bulbs over the winter, and he recommends giving them a very thorough watering immediately they are planted up.
He makes sure that the water has stopped dripping from the bottom of the pot before storing them away and doesn’t touch them again until the spring.
Winter Storage
Spring flowering bulbs all need a period of about three months of cold. This makes the bulb split the stored glucose into smaller molecules that help withstand freezing. Leaf structures and the cells for flowers begin to form as well during this time.
The problem arises when there are constant freeze-thaw cycles, which we definitely have in our area. The bulb doesn’t know if it’s coming or going and is likely to end up rotting unless something is done to offset the variations in temperature.
The key is to keep the temperature as even as possible, and certainly below about four to five degrees C.
Michael stores his pots in closed cardboard boxes in an unheated garage. There is enough protection there to keep the bulbs cold enough but at a fairly even temperature.
Jennifer has another method: she waters the pots lightly and puts them outdoors for the winter in a sheltered, shaded spot, and then mounds leaves and fir boughs all over them. Great success here too!
Other options are using bubble wrap, old blankets or even digging the whole pot into the ground and covering them up with leaves or compost.
The point is that in our climate the pots have to be protected one way or another
It is also useful to consider that mice and squirrels might come for a yummy snack. Adding chicken wire or hardware cloth over the pots would help here if it is a problem.
When things start to warm up in the spring, keep an eye out for the tips of the bulbs to start poking through the soil. That’s the signal to bring the pots out to a place where there are cool temperatures and indirect light.
When they are advancing nicely and the weather is definitely warming up, you can place them in their final containers and positions.
The two great enemies when storing potted bulbs are:
large temperature fluctuations and too much moisture.
The End of the Cycle
It is quite common to treat pot-grown bulbs as annuals. You just throw them out when they have finished blooming and start anew in the autumn.
There are many reports that you never quite get what you had in the first year if you keep the bulbs in the pots, particularly with tulips. So another option is to take the bulbs out of the pot and plant them in the garden, feed them with a bulb fertilizer and water from time to time. You can, of course, use the lasagne method in the garden bed too!
If you do want to save your masterpiece in the pot for next year, take off all the dead flowers, place in a sheltered spot outside, water sparingly, but leave the foliage until it has turned yellow or brown.
Finally, remove the dead foliage, give it all a liquid feed, and put a new layer of potting soil on the top. Keep the pot in a shaded spot and water carefully over the summer. The overall point is to build up the bulb so it can support another year of flowering.
Come autumn you can start the whole process all over again. Hooray!
VIVA LASAGNA!
Copyright©2024 Elizabeth Spence