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!).
A customised fertilizing program keeps plants healthy and resistant to pathogens and pests and also cuts down on the use of chemical control agents. Proper fertilizing also ensures a good soil structure. There is a choice of fertilizing agents: - Compost and manure. These are organic fertilizing agents. As described previously, they are also effective in improving the soil. - Organic supplements that provide a complementary balance to organic fertilizing agents. - Compound mineral fertilizers The type of fertilizing agent chosen depends on the kind of planting and the time at which the agent can be applied. For more information, please have a look in the landscape brochure.
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.
Dahlias are cultivated primarily in the Netherlands. Most of these growers are located in the Bulb district / De Bollenstreek. Other regions where dahlias are cultivated are the western coasts of France and the United States / western coast of France and in the United States.
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.
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.
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.
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.
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.
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.
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.
Squirrels can be terrible pests! They won't bother daffodils and other narcissi bulbs (which taste terrible to them!), but they find tulips and crocus in particular to be worth the effort to sniff out and dig up. The only sure-fire way to protect tulips and crocuses and other tasty bulb treats from squirrels is to lay wire mesh such as chicken wire on top of the bed. The squirrels can't dig through the mesh and the flowers will grow neatly through the holes. Bulbs are most vulnerable in autumn immediately after planting when the soil is still soft and worked up. Digging then is easy! Squirrels often "chance" upon bulbs when burying their nuts in soft ground. Or they are attracted by "planting debris" such as bits of papery bulb tunics and other bulb-scented bits from the bulb bags. Don't advertise your plantings. Clean up and keep those squirrels guessing! Here's one trick that garden writer Judy Glattstein has found to work. After planting new areas, lay old window screens in frames on the ground, covering the newly-worked up soil. The screen weighs enough to foil the squirrel, but allows for air circulation and rainfall. Once the ground has settled, remove the screens and store for future use. Another remedy that some find successful is to actually feed the squirrels during the autumn and winter. The theory is that the local squirrel population, when offered a handy plate of peanuts or other easy-to-get treats will leave your bulbs alone. At the White House, the gardeners put up six peanut-filled feeding boxes to satiate the furry denizens there -- and reduced squirrel damage on bulb beds by 95 percent! Many gardeners claim success with commercial repellents, but these are often sticky and unpleasant to deal with or wash away in the rain. Home remedies include sowing cayenne pepper into the soil or on the bulbs before planting and scattering moth ball flakes on the ground. You will find advocates and detractors of both methods. A favourite Dutch remedy is to interplant Fritillaria imperialis. This tall dramatic plant gives off an odour that squirrels (and deer too, reportedly) find repellent. There is a book on the subject, "Outwitting Squirrels," by Bill Adler, Jr. (1988 Chicago Review Press, Chicago, IL). It's aimed at owners of bird feeders, but you may find some helpful hints.
This formula – the “Spring Meadow” – has actually been realized at Keukenhof gardens in Lisse. Keukenhof is the largest flower bulb display in the world. In April and /May 7.million flower bulbs colour this great place and it delights thousands of visitors every year. At a number of sunny places in the lawn, wave-shaped areas were cut out of the sod to a depth of more than 10 cm (4 inches). These shapes were filled with sharp sand that was then mixed together with the soil below and above it. This created perfect spots to plant small bulbs for naturalising: over a surface of around 500 m²/600 square yards, 55,000 bulbs composed of 35 different kinds were mixed and scattered and then planted by hand. At the Keukenhof, the planting of these bulbs was also accompanied by the sowing of a flower meadow seed mix so that the bulbs would emerge among a haze of herbaceous plants that would then provide weeks of colour once the bulb flowers had faded. Any bulbous plants suitable for naturalising that also have a more or less “uncultivated” look can be included in this kind of mixture. The flower bulbs used for the Spring Meadow at the Keukenhof were distributed at a rate of approximately 150 bulbs/m² or 180 bulbs/square yard and were made up of the following varieties: • Bellevalia pycnantha • Chionodoxa forbesii • Chionodoxa luciliae • Crocus tommasinianus 'Ruby Giant' • Crocus tommasinianus 'Whitewell Purple' • Leucojum aestivum 'Graveteye Giant' • Muscari aucheri 'Blue Magic' • Muscari 'Valerie Finnis' • Narcissus 'Jack Snipe' • Narcissus 'Jetfire' • Narcissus poeticus recurvus • Narcissus 'Topolino' • Ornithogalum umbellatum • Scilla siberica • Tulipa bakeri 'Lilac Wonder' • Tulipa clusiana • Tulipa clusiana 'Lady Jane' • Tulipa linifolia • Tulipa tarda • Tulipa urumiensis
Flower bulbs planted in these locations have to be strong enough to “go it on their own”, in other words, to be able to take care of themselves between such powerful competitors. In addition, the kinds that flower earliest are often the kinds chosen for these sites since they are easily visible among the woody plants that are still bare. Perfect here would be a mixture of at least six varieties of naturalising bulbs that have successive flowering periods. Such a combination planted in variously sized clusters in the lightest spots in a wooded area or along the edge of a wood will ensure years of flowering that becomes increasingly profuse year after year.
Tulips planted for multiple-year flowering should be deadheaded once the flowers start to fade. This prevents the development of seedpods, a process that uses the plant’s energy resources to produce seeds instead of new bulbs. Deadheading is the name given to breaking the flowers off from the stem. This also prevents petals from falling into the leaf axils and allowing Botrytis to develop.
As a rule, mowing grass strips containing flower bulbs is not started until an average of 6 to 8 weeks after flowering. Grassy areas planted with flower bulbs can be mowed only after all the aerial parts of the bulbs have withered back. Some flower bulbs such as Chionodoxa, Scilla and Eranthis propagate by seed, so their seeds should get a chance to mature.
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.