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 German books on water gardening usualy mention lotuses only with a few sentences and regard them as unsuitable for our climatic conditions. In one book we found the ‘masterstroke’ in the reduction to just one sentence: ‘Lotus originates in Ceylon and is not hardy.’ – illustrated with a picture of the North American native lotus. There are lotuses in Sri Lanka (it seems the author used a very old map) but certainly not the one shown in the picture. The most northern populations of lotus in the wild can be found in the Great Lakes in North America and in Lake Khanka in Siberia (about 200 km north of Vladivostok). Both regions experience severe winters – which lotus obviously doesn’t mind.
 Meanwhile we solved the puzzle why German books so stubbornly insist that lotus is not suitable for our gardens. In 1913 a ‘imperial and royal’ court gardener in Vienna tried to grow lotus in one of the parks. The only lotuses available at that time were the Marliac hybrids. While Marliacs waterlilies do marvellous, his lotuses don’t. Even in warmer climates they are at best moderate bloomers. Supposedly this court gardner had no experience in growing lotus, and it may have been a cold year. In the end he was not very successfull and published his experiences and conclusion in a horticultural magazine: ‘the cultivation of lotus north of Vienna is impossible!’. Since horticultural literature is propagated in a vegetative way by copying from other books, this conclusion was passed on for generations. No one every bothered to verify it.
Lotus in Central Europe
 Lotuses are hardy in Central Europe if their rhizomes do not freeze solid over a longer period of time. In this respect the do not differ from waterlilies. If provided with 30 cms of water above and 30 cms of mud below the rhizomes, it will survive all but the most severe winters without any further protection. There are naturalized populations of lotus in northern Italy where winters can be very cold. They do not only survive there, they are even invasive and cause problems. The picture shows one of the lakes of Mantua, the light green line in the lake are thousands of lotuses. If you ever come to Mantua, take a look at the lake and you will be impressed.
Growing Lotus in Tubs
 If this is true, why is lotus no common plant in our ponds? The reason are our summers, they are too changeable. In an average year temperature slowly rise during spring and so does temperature in the pond. By the mid of May water temperture of the Atlantic has risen so much that more and more water evaporates and heavy clouds do form – the first monsoon wave rolls over Europe, a phenomenon known in Germany as the ‘Ice Saints’. Even if the ‘Ice Saints’ usualy no longer do bring frost nowadays, they bring a period of cold rain. For days ice cold water rains into the ponds and water temperature drops dramatically. The weeks to follow weather becomes milder and temperature rises again. In June we experience the second monsoon wave (in Germany called ‚the sheep’s chill’ – for it appears at the time of sheep shearing) and once again temperature in the ponds drops. By the end of June it turns out if it will be a good summer with six to eight weeks of sunshine, or if also the remaining part of summer will be a chain of monsoon waves.
 To induce flowers lotus does need a certain amount of hours with water temperatures above 20° C. How many hours it needs depends on the variety. There are early and late blooming varieties. One good thing is that the hours above 20° C do not have to be connected. The plant ‘keeps book’ of the suitable hours and as soon as the full amount is reached, it starts to bloom. In a rainy year this is of little help, for the water in the pond simply needs to long to warm up. Therefore we recommend the cultivation of lotus in a pond only in region with warm summers, like in vinegrowing region in Central Europe. In all other regions we recommend to cultivate lotus in tubs, just like the Chinese use to do. A tub contains just a small volume of water. After a rainfall water temperature in the tub rises much faster than in a pond. Usually a few hours of sunshine are enough to rise the temperature above 20° C. The plant will continue to ‘count’ the units of warmth and will start to bloom when its ‘account’ is full. Winterizing the tub is easy, you can do it in a cold room that may be even completely dark.
Basic Needs of Lotus
Lotus has the same needs like a baby: food, warmth and cleanness. If it gets them in sensible amounts it will grow perfectly.
Fertilizer is food for lotus. It needs enough, not too much. Overfed babies are not healthy.
Warmth in this case is water temperature. Lotus likes the same temperatures that humans like. It doesn’t like temperatures below 20° C or above 30° C. The plant doesn’t want to freeze or too sweat.
Cleanness means clear water. If the water turns green or murky, it is a sign that there is more fertilizer in the tub than the lotus can use. On the long run dirty water and putritidy will kill a lotus.
The Tub
 We grow all our lotuses in round 65 liter mortar tubs made of black rubber. This size proofed perfect for us. It is large enough to house also the larger varieties and small enough to handle and transport it without machines. For dwarf varieties you can use smaller tubs, but 20 liters are the absolute minimum. It is important that you use round tubs, since lotus rhizomes often get stuck in corners. The literaly do not find the way out of the corner and die.
Those black mortar tubs from the hardware shop are cheap and handy, but admitedly they are no beauties. The tubs may be put into larger cache-pots, or they can be covered with rush mats or something else. If possible choose dark colours for the cache-pot, it helps to warm up the water more quickly.
Growing Medium and Fertiliser
 It is not necessary to use a spezial growing medium, lotus can deal with a wide range of soils. We started our nursery on a property where the soil was very sandy had a pH of 7.8. After the relocation of the nursery we now have almost black soil without any stones or sandy, pH is 6.3. Both kinds of soil worked well with the lotus. So in most cases you will be able to use the ordinary soil that you have in your garden. Not suitable is peat, compost or bark mulch, for they cause putritidy. Mixed composts out of a bag are usualy composed of peat, they are not suitable for lotus, also if ‘special mixture for pond plants’ or something similar is written on the bag. If your soil is too light to hold the lotus (the rhizomes do have a very high buoyancy) you can make it heavier by adding loam, powdered clay or bentonite.
Organic fertiliser like manure is unsuitable for lotus. It is true that it is often used for lotus in China, but it causes unbelievable stink. It is also easily overdosed and will then burn and kill the lotus. Slow release mineral fertilisers are perfect for lotus. Lotus is a heavy feeder, but it can be overfed. With a slow release fertiliser it is unlikely to overfed the plant. We add the first dose of fertiliser to the soil during planting and re-fertiliser three times during summer.
How to plant Lotus
 Lotus can be planted from late March to early June. The best time is from April to mid May.
At first fill the tub to one third with growing medium that was mixed with fertilizer. If you use the fertilizer cones we sell, please add six cones (= 30 grammes) to the soil for large lotus varieties and four cones (= 20 grammes) for medium and small varieties.
This layer of fertilized growing medium is now topped by an equaly thick layer of unfertilzed growing medium. The rhizome might start to rot if it is in direct contact with the fertilizer, so this topping layer is a protection for the rhizome. Roots that develope from the rhizome are not that sensitive and will grow down into the fertilized layer and start to feed the plant from there.
Now fill the tub with warm water untill the medium becomes soggy. There should be no water covering the medium, for it is important for the next step that you can clearly see what you are doing.
 Lotuses do have rhizomes that look like a somewhat thin banana. One side of the rhizomes ends in a cut (the ‘dead’ end), the other side ends in the shoot. The new plant will develope from this shoot. When handling the rhizome it is important to keep in mind that it has no flexibility at all. In this respect it is very similar to Asparagus. If you bend fresh Asparagus you will soon hear a ‘snap!’ and the Asparagus is broken. If you pull at fresh Asparagus however, you will find it is astonishingly tough. Lotus rhizomes do behave very much like Asparagus. When planting Lotus please avoid any pushing or forcing down. It is better to hold the rhizome at the ‚dead’ end and pull it into the wet soil. If the rhizome breaks during planting, it will die.
How to get the rhizome safely into the growing medium
 What you need most for planting Lotus are time and patience. At first lay the rhizome onto the soggy growing medium. With your flat hand follow the shape of the rhizome and form this way a drill that is somewhat longer than the rhizome. Now hold the rhizome at its ‘dead’ end and pull it into the drill. In most cases the wet soil will hold the rhizome now. It is up to if you prefer to fix the rhizome by using a U-shaped wire (like a huge hair pin) or to cover carefully the rhizome with some growing medium. However it is important not to cover the shoot. When the rhizomes sits in the growing medium the tub is filled with lukewarm water. There should be about 10 cms of water above the growing medium. If the rhizome floats up you have to replant it. In this case the either the growing medium was to light (add some ground clay) or you didn’t cover the rhizome with enough medium.
Care of the Lotus after planting
 Your Lotus is now planted and the tub is filled with water. Until the mid of May (mid of June in very cold regions) your Lotus prefers a location with much light and temperate conditions. It is sufficent to provide temperatures that are just a few degrees above temperatures outside. Suitable places are poly tunnels or greenhouses for tomatoes, conservatories and rooms with plenty of sunlight. If you have to choose a place that might be hitten by late frosts, you may want to consider the use of an aquarium heating element that protects the tub from freezing. Your Lotus will now start to grow and its ‘internal clock’ will start to count the hours with temperatures above 20° C. Depending on the variety all Lotuses need a certain number of hours above 20° C to start flowering. About half of those hours the Lotus will collect during the protected preparatory culture indoors. When the Lotus is moved into the garden in summer it will collect the rest of the needed hours there.
 Temperature shouldn’t be too high for Lotus. Lotuses are plants of the the subtropics, not of the tropics. What matters are hours above 20° C. Lotus kept at 21° C will take as long till flowering as one kept at 28° C. Lotus can’t deal too long with temperatures that are too high. Greenhouses and conservatories heat up quickly in late spring and if they are not ventilated, temperature may reach degrees that will kill your Lotus. 25° C are more suitable for Lotus than 30° C are. In an unvetilated greenhouse temperature can go up to 50° C and your Lotus is simply boiled to death.
Lotus is fertilized three times during the summer. It is important to fertilize not later than mid of July, else the rhizome won’t be mature when winter rest starts. We plant our Lotuses at the beginning of April and fertilize early May, June and July. The first time we add 3 more fertilizer cones, the second time 2 cones and the last time 1 cone. So the regime of fertilizer is 3-2-1 at intervals of one month. The fertilzer cones are simply pushed into the topping layer.
Care during summer
 During summer Lotus is best kept in the garden. Chose a situation that provides a lot of sunlight and that is protected from wind. In most cases this place will be your patio. A porch may be of benefit; during longer periods of rain you can put your Lotus under the shelter of the porch. If you prefer to keep the Lotus close to the pond, you can dig a hole in the size of the tub just beside the pool and sink the tub into this hole. Soon the foliage of the Lotus will completely cover the tub and the Lotus will appear to be part of the pond. Care during summer is restricted to replenishing evaporated water, cutting gone leaves and flowers and fertilizing. It is important to deadhead spend flowers immediately. If Lotus is allowed to set seed, it will stop flowering.
Winterizing Lotus
From November on Lotus should be brought to its wintering place. Lotus does need a cold winter rest. Please do not try to keep Lotus warm and bright during winter, it wouldn’t survive. The best place for Lotus in winter is a cold room, it may even be a room without light. Even slight minus temperatures now and then do no harm to your Lotus. We think that in most cases your garage will be the perfect place to winterize your Lotus. Cut off all parts of the plant just above water level. Put a styrofoam board on the floor in a corner of the garage and place the tub with the Lotus on it. Fill up water to the rim and wrap the tub into bubble wrap. If you lay a wooden board across the tub you can even store other things on it – for example the summer tyres of your car. That’s why Lotus got the nickname ‘tyre-change-plant’ in our nursery. It is moved into the garage when it is time to mount the winter tyres, and it leaves the garage in spring when it is time to mount the summer tyres.
Dividing and replanting
After two or three years your Lotus will be too big for its tub and has to be divided in spring. For this work you should choose a spot in your garden that may get really dirty and wet. Turn the tub upside down and pull it from the Lotus (just like turning out a cake). What you will see is a clump of dirt with the rhizome inside. The rhizome is now much bigger than the piece you purchased from us. Take the garden hose and wash of all soil this the rhizome lies bare in front of you. The rhizome is composed of two different elements: thinner parts that have equale diameter all over their lenghts (the are called runners and no new plant will grow from them, so you can discard them) and parts that look like a chain of sausages (this are the new rhizomes and that is what you want to replant). Cut away carefully the rhizomes from the runners. You find the right place for the cut by counting the ‚sausages’. Between two ‘sausages’ there is always a constriction. It works like an outlet and keeps water from entering the rhizome if it is damaged. Search for the tip of a rhizome, count two ‘sausages’ from the top and cut after the following constriction. You now have a rhizome that can be replanted. In most cases you will gain several new rhizomes from your Lotus.
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Lotus in conservatories
You can keep your Lotus in the conservatory during the whole growing period. It will set flowers there even during cold summers. It is very important that you provide your Lotus a cold winter rest. Also Lotus kept constantly in a conservatory should be brought to a cold room during winter. Else it may grow on untill all its forces are spend and it will die.
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