Bulb FAQs

Should I apply mulch? How deep? When?
Should I fertilise bulbs?
Is it true that bone meal is the best bulb food?
I have seen the same variety of bulb priced very differently, some very cheap and others quite expensive. What's the difference?
I've been told to plant bulbs in clusters - why is this important?
How soon should I plant my bulbs after I buy them?
When do bulb growers in the Netherlands plant their bulbs?
What is the Flower Bulbs Quality Mark Foundation Holland (SKBH)?
In which country are dahlias cultivated?
Are there really so many crop protection agents used in the bulb-growing sector?
Why are tulips grown in Holland of all places?
What are the dates for the Ice Saints' days and why are these dates important?
Are there bulbs that scare off mice and/or rats
Why do we have to pay VAT?

Should I apply mulch? How deep? When?: Mulch is not required but it is often beneficial. Three inches is plenty. Wait until the ground cools down. Contrary to popular notions, mulching over bulbs is meant to retain soil moisture and keep the ground temperatures cool and stable, not to serve as a "warm winter blanket" (except in the very coldest climates). Mulch just before the ground freezes. Applying mulch too early in the season, when the ground is still soft and warm, can invite infestations by field mice and other critters who like to burrow in to establish winter quarters (and no doubt dig up tasty tulip treats!).
Should I fertilise bulbs?: If you're planting bulbs for only one year's bloom, fertiliser is not needed. Bulbs already carry a season's supply of food in the moist tissue surrounding the embryonic flower. For bulbs that you will naturalise or perennialise, you have the following options:

At autumn planting time:
For first year's bloom, no fertiliser is needed.
For naturalised bulbs after the first season, there are three good options:
A good organic compost or well-rotted cow manure worked into the soil when planting and a mulch of this material,
A slow-release bulb food,
A combination of bone meal and an 8-8-8 or 10-10-10(NPK), fast-release soluble fertiliser (about one tablespoon per square foot).

In spring:
Again, for first year blooms, no fertiliser is needed.
For naturalised plantings or perennialising plants, fertiliser considerations are:
Nothing further is needed if last autumn you applied well-rotted cow manure or a slow release bulb food.
If you used bone meal and a fast-release fertiliser, you will want to apply a nitrogen-rich fast-release NPK fertiliser in the spring just as the shoots first emerge from the soil (which would be about 6 weeks prior to bloom).
Is it true that bone meal is the best bulb food?: Once upon a time, bone meal was considered an excellent bulb fertiliser, but times have changed! Most bone meal today has been so thoroughly processed that the essential nutrients have been literally boiled out. Spring-flowering bulbs actually need no fertiliser for their first season of blooming. A healthy Dutch bulb will already contain all the food it needs to support one season of spectacular growth. Bulbs that will be left in the ground to naturalise will benefit from well-rotted cow manure or special bulb fertiliser when the shoots first appear in spring and again the following autumn.
I have seen the same variety of bulb priced very differently, some very cheap and others quite expensive. What's the difference?: In the auctions in Holland, bulbs are gauged by their calibre, or the measurement of the bulb's circumference. For each particular variety: more mature bulbs are larger and garden bigger flowers. These demand a higher price. For high-profile bed plantings, it's worth the higher price for the more mature, "showier" bulbs. But younger (smaller calibre) bulbs, which are often sold at lower prices, can offer a great way of adding colour to large areas or marginal areas of the yard where they can be left in place to naturalise and mature, thus gaining in size over time.

A note: for quality control reasons, the Dutch do not export bulbs below certain established calibre's. For instance, tulips must be 10 cm or larger or the Dutch will not export them. This means that if you see tulip bulbs for sale that are smaller than 10 cm, they are not from Holland. No exceptions are allowed... except for species tulips, which are naturally sized smaller.
I've been told to plant bulbs in clusters - why is this important?: Groups of bulbs make a much nicer show than individual "soldiers marching single file." To create greater colour impact in the garden, plant clusters of same-colour flowers together in blocks or "bouquets." One trick: try positioning similar bulbs in a triangular planting pattern in the garden, with the point of the triangle towards the front and the long leg towards the back. The result: it will look as if you planted more flowers than you did.
How soon should I plant my bulbs after I buy them?: Sometimes you will buy bulbs before you are ready to plant in order to get the best selection. While it's always best to plant your bulbs as soon after you receive them as possible, when you have to wait, be sure to store the bulbs in a cool, dry place away from direct sunlight. Some people keep their bulbs in the refrigerator crisper drawer, taking care to avoid storing them with ripening fruit. They should be fine for several weeks even months if properly handled. But don't wait too long. Ideally, you should plant six weeks or so prior to hard ground frosts in your area to allow ample time for autumn root development.

A tip: the proper time to plant is when ground temperature is below 13°C at planting depth (while this is not easy for most of us to gauge, it gives you some notion of what's appropriate). If you don't have six weeks lead-time, plant any way even if you have to hack your way through hard, chilled surface soil. (As always, be sure to water.) The key: you must plant in autumn to have blooms in spring. Even if planted late, bulbs will spring into action and try to start root growth. They are pre-programmed to grow and will do their best no matter how late you plant them.
When do bulb growers in the Netherlands plant their bulbs?: Growers in the Netherlands plant their bulbs in November. They can do this because winters in the Netherlands never really start until mid-December. In regions where the winter starts earlier, it would be advisable to plant tulips in October.
What is the Flower Bulbs Quality Mark Foundation Holland (SKBH)?: The Flower Bulbs Quality Mark Foundation Holland is a foundation that was established to offer consumers an independent sounding board for any complaints that might arise. You can thus contact this foundation if your bulbs have not provided the desired results. Sending a photo along with a complaint is not obligatory but can definitely support your position. You can also submit a complaint if the bulbs you purchased produced flowers other than those indicated on the packaging. Just make sure, however, that the SKBH logo appears on the packaging.
In which country are dahlias cultivated?: Dahlias are cultivated primarily in the Netherlands. Most of these growers are located around the Bulb Research Centre (LBO) and companies that select new varieties. Other regions where dahlias are cultivated are the western coasts of France and the United States.
Are there really so many crop protection agents used in the bulb-growing sector?: The use of crop protection agents for bulb cultivation has dropped dramatically over the last ten years. Both research efforts and commercial practices have shown that it is possible to produce bulbs by relying much less on these agents than was previously assumed. This not only benefits the environment but also decreases the growers' costs. By applying a perfect balance of fertilisers, the bulbs receive sufficient nutrients while much smaller quantities of hazardous substances are discharged into surface waters. Where preventive spraying for such problems as fungi used to be the norm, today's practices advocate spraying only when necessary. Where possible, many bulb-growing companies are beginning to use organic means to prevent diseases and pests.
Why are tulips grown in Holland of all places?: Tulips were introduced into the Netherlands at the end of the 16th century by Carolus Clusius. People in the Netherlands were quick to take an interest in these bulbs and started experimenting with growing them in the gardens around their homes. Because the demand for tulips grew, an increasingly professional approach was devoted to their cultivation, and it turned out that the coastal area - and especially the strip of land just inside the Dutch dunes - had the perfect conditions for this. The marine climate with its mild winters and cool summers, proper drainage with a consistent water level, the right type of soil and the fact that the Netherlands was a centre of trade were all very beneficial factors. With the increasing urbanisation occurring in the traditional bulb growing regions, the most important growing areas today are located in the northern regions of the Netherlands where there is still enough land available for bulb growing. This will assure their cultivation in the Netherlands for a long time to come.
What are the dates for the Ice Saints' days and why are these dates important?: The Ice Saints' days recognised in certain European countries are 11, 12, 13 and 14 May. These are the saints' days for four saints: St. Mamertus, St. Pankratius, St. Servatius and St. Bonifacius. Because three is a holy number, however, one of these (either St. Mamertus' day on 11 May or St. Bonifacius' day on 14 May) has been eliminated, depending on the country in question. The Ice Saints' days indicate the end of the chance of frost even though long ago, ground frosts still occurred after these days. In general, the arrival of these dates signifies that it is safe to plant summer-flowering bulbs.
Are there bulbs that scare off mice and/or rats?: Unfortunately, no bulbs have the capacity to really scare off mice or rats. There are a few precautionary measures that can be taken to keep these pests from eating your bulbs, however. First, plant the bulbs deeply enough and cover them properly with soil so that mice and/or rats are not attracted to the planting site. Secondly, cover the border where the bulbs have been planted with some finely meshed wire netting. Lay out this netting so that it more than covers the border and then insert the edges slightly into the soil.
Why do we have to pay VAT?: We supply our bulbs to a large cross section of users, many of which are large companies, local authorities, contractors or organisations. We have to keep Value Added Tax separate for these customers.Now we offer our bulbs to private users and we will treat these orders as we would those from our commercial customers.

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