Advantages Of Storing Begonia Tubers As Root Balls

Many begonia growers brush their tubers off before storage. I have never had much luck with this method. I always store mine as a root ball complete with soil or compost, and find it has advantages.

ADVANTAGES FOR STORING
Although I stop watering my begonias in pots around the start of October, I still find they do not really dry out. Consequently, it is for me almost impossible to clean them without breaking the tubers or damaging them in some way. So I just place them in an airy spot to dry them as much as possible before storage, then don't cover until the really severe weather comes. They seem to store well this way with little or no disease problems. We covered lifting begonias last year.

ADVANTAGES FOR PLANTING
Once it becomes clear in early spring that tubers are showing signs of growth, root balls can be watered lightly and placed in a light frost-free place. This helps them along and avoids the need to pot up the larger tubers which are almost impossible to fit into almost any pot.

BEWARE OF VINE WEEVIL GRUBS
The tuber above has been treated as described and can now be planted as it is. However, it will need some treatment for vine weevil grubs which will almost certainly have overwintered with the tubers and will be hiding in the roots somewhere. I use 'Provado Vine Weevil Killer', a stronger dose of thiacloprid.

Several Geotropic Shoots From Nodes Of Horizontal Dahlia Stem

This is the dahlia stem we planted horizontally three weeks ago to make it more drought-resistant. Shoots, being positively geotropic, grow upwards towards the light. Here we have several shoots, each springing from a node of the horizontal stem. Because these nodes are all at the same height, just below the soil surface, they have more equal access to its water reserves.

Dahlia Tuber Wheels Produces Several Shoots

Several shoots are now visible on one of the dahlia tuber wheels planted in April (see 'Can A Dahlia Tuber Wheel Produce New Plant Vigour').



Although we now know the technique works, there have been two problems:

• slugs

• poor nutrition in deeper holes

SLUGS
Wet warm weather is perfect for all kinds of slugs and snails. I had earlier treated the bed with organic slug pellets and therefore assumed it was clear of the pests. Unfortunatley not. Small garden slugs did great damage in the deeper holes, almost from the off. Had to revert to Metaldeyde pellets, which cured the problem (although, in fairness, I have to say that organic pellets seemed to work on the delphiniums earlier. a problem with organic pellets is that because the slugs go away to die, it's impossible to tell whether or not they have worked - until it's too late.)

POOR NUTRITION IN DEEPER HOLES
It's very easy to become too enthusiastic when trying out new concepts and ideas. This was such a case. As you can see, the leaves are rather pale, so this could indicate a lack of nutrients (it could also be other things, such as cold - or just because it's new growth).

I think this is because I got clever and failed to place the tubers on multi-purpose compost (I was short of it at the time), as recommended. This would have supplied all the nutrients necessary for healthy strong growth, as it did last year. Soil is most fertile in the upper 'A' horizon, usually within the first 15 to 20 centimetres (6 to 8 inches) where the micro-organisms are most active (due to adequate air).

THE GOOD NEWS SO FAR
Because several shoots are now growing up through this fertile 'A' horizon, the adventitious roots produced on the new stems will have easy access to soil nutrients in this area, something they otherwise would not have done. Thus, using this technique offers a kind of insurance policy against poor conditions.

Bedding Plants: Common Mistakes - Part One

The last weekend in May is traditional planting time in the UK for summer bedding plants. Amazingly, something which should be straightforward often ends in failure. Here are some of the common mistakes:

• poor quality plants
• wrong weather conditions
• wrong time of day
• poor watering technique
• feeding at wrong time
• wrong feed
• poor after-care

POOR QUALITY PLANTS
They say one cannot make a 'silk purse out of a sow's ear'. How true. Start with good strong plants, avoiding:

• end-of-line bargains (unless you know you're doing)
• plants which do not look healthy (leaves should be unblemished and uniformally green)
• dehydrated plants (leaves should be erect, not limp)
• weeds growing in pot

Many add pot-bound plants (thick roots growing strongly through base of pot) to the list. You can actually use these. But demand a discount, because there will be a growth set-back once you have cut them out of the pot (never pull plants out by holding their stems or leaves - after slicing off protruding roots level with base of pot, invert pot onto palm, then push base of pot with thumb of other hand; you might need to cut around rim with a knife first, but avoid this, if possible).

WRONG WEATHER CONDITIONS
Visit a garden centre during a spell of rainy weather and it will be devoid of customers. Some gardeners are like those couples in ornamental weather houses - you know, the ones attached to catgut who only venture out when the weather is about to turn dry and sunny. Yet a prolonged spell of overcast, showery weather provides near perfect conditions for planting, especially if the soil has received sufficient water to get down a foot or two.

Work with the weather if you can. Choose an overcast day, then rush out and plant between the showers - it pays dividends (if you can avoid contracting pneumonia)

If the weather is too hot and rain is forecast, delay planting till then. Have everything prepared. And DON'T FORGET THAT HOT, CLEAR WEATHER OFTEN MEANS OVERNIGHT GROUND FROST, so cover plants at night with horticultural fleece till they are hardened off (fleece is also good for shading from sun)

WRONG TIME OF DAY
Humans being humans, we cannot resist rushing out in the burning mid-day sun to put our plants in the ground, as if we are somehow doing them a favour. No! No! No! Plants are averse to burning sun and even to heat. The best time to plant is at the end of the day, preferably when rain forecast (you will need to watch out for slugs). This was covered last year in 'Resisting the Heat'.

POOR WATERING TECHNIQUE
Most of this has been covered elsewhere (click 'starters' link at side). But what I want to tell you is this:

• As much water should be given to your plants BEFORE planting as possible. This is not generally understood.
• No matter how careful you are, there will always be some impairment to root functioning caused by the disturbance.
  
• Also, roots need air around them to function well. So waterlogged soil is no use.
  

Before Planting
Therefore, give your plants a good soaking at least four hours before planting. This will give time for enough water to be taken up to sustain establishment after planting, and also to allow any excess water to drain away from around the roots, thereby allowing them to function well right from the off.

Make sure the ground is thoroughly wetted, down to at least 30cm (1 foot), if possible. As I have told you elsewhere, dry ground is notoriously difficult to wet. Make sure any water you apply does not run away through cracks in the soil, or even run off the soil surface.

After Planting
Preferably do not apply water; otherwise, give a good dousing. Then refrain from watering as long as possible (even to wilting point). Plants can sense moisture levels; as these diminish they send out roots to look for it. If water is given too early, the roots become lazy and do not develop, consequently leaving the plants more drought-susceptible.

Beware of panning or puddling the soil surface, especially on clay or silt soils in hot sunny weather. This mud dries hard and seals out air vital for root development. If this happens, allow to dry, then break up the hard surface.

Ongoing Watering
DO NOT WATER ON A DAILY BASIS. Leave the soil to dry out for at least a few days. As water is taken up by the plants, air is drawn down to the roots to take its place. Repeated soaking followed by drying encourages a good root system (remember the geranium?). As a rough guide, let surface dry out down to about 5cm (2 inches) between waterings, then apply 5 litres per square metre. A fine watering rose and gentle pressure should be used.

FEEDING
DO NOT APPLY ANY FEED WHATSOEVER at this stage. There is no way of knowing how much feed is already in the compost; there is also no knowing whether or not dry weather will return.

PLANTING TECHNIQUE

Gently firm plants into loose soil with knuckles, so they are adequately supported. Do not apply too much pressure, try to avoid damaging roots and do not handle by stems or leaves. Watch out for slugs and frost.

P.S. Most of the above has already been dealt with in the earlier posts of last year. It's worth having a look.

Planting Begonia Tubers: Beware of Personality Change When Watering

Great care is needed when planting begonia tubers, since they have a personality change at this stage. Normally thriving on wet conditions, they hate them at germination time. Too much water at planting will rot the tubers. Watering should be done before planting to ensure correct wetness of compost.

HOW WET SHOULD COMPOST BE?
The same as required for germinating cuttings: so that water just appears between the fingers when squeezed hard in hand, but is drawn back into compost when grip released. Think of a freshly-wrung-out face cloth.

PREPARING TUBERS
This tiny begonia tuber is all that is left of the one you saw recently in a 5 inch pot.

After removing the old diseased (grey mould - botrytis) stem and treating wound with yellow sulphur powder, I also carefully removed the old dry compost from around the tuber. Now there is hardly anything left. I now regret doing this; it might have been better to leave the old compost on.

Prepared some fresh compost in a 3.5 inch pot as described above and planted tuber up to neck. Placed in propagator with others.

Will have to watch out for botrytis re-appearing in humid conditions.

Daffodils in Pots Planted

Lifting the dahlias has made room for spring bulbs. The bulbs planted in pots have now rooted and have been planted 20 cm (4 inches) below the top of the bulbs. There is no sign of shoot development yet.

Out With the Old

Couldn't stand looking at stunted tomato plant any longer. Hoofed it out and replaced with one of side-shoot cuttings taken from same plant (removed before problem occurred). As you can see, roots look O.K .- Not fantastic, but O.K (i.e. white, not brown, with some growth and thickening).

Problem must be either weedkiller or a virus. By placing cutting in old compost, should tell us whether compost is suspect (planted the other of the two cuttings in new compost).

Planting a Cyclamen Corm

This cyclamen corm is beginning its fifth year. After flowering finished in May, it was dried off (as it stood, in the pot, complete with leaves), then removed from pot, and old dry compost carefully removed.

Cyclamen is one of those plants that do not like water on their crowns ('African Violet' is another). So when planting, crowns need leaving proud of the compost. In this case, I selected the smallest pot which would contain the corm, filled it with wetted multi-purpose, then worked corm gently into surface so compost level only slightly above roots.

Note: Compost should be wetted but not saturated (water should run out between fingers when squeezed in hand, then retract when released).

If you have a cool humid window (e.g. bathroom) which receives some morning or evening sun, this plant is ideal. I have had best results when kept cool (kitchen can get a bit too hot). It will then flower for about eight months. And it smells gorgeous.

Resisting the Heat

As tempting as it is during a spell of hot weather to rush out into the garden in the heat of the day and put in the bedding plants, we need to bear in mind one thing: Most plants do not like hot weather, especially when they are very young.

So, if you can restrain yourself 'till evening, when the sun is weaker, this is the best time to plant. But make sure everything has been well-watered first. And water again after planting.

But what if you just cannot wait? What if mid-day is the only time available?

Well, get yourself some sheets of newspaper, or kitchen towels (split each into 2 layers) and pop these over the top of the plants to keep off the hot sun, just for a few hours. It will work wonders. And you can wet them if you wish.

It's a pity newspapers look so unsightly, because they make a wonderful insulator for the soil, as they reflect the sun's rays. They are also porous, moisture-retentive and biodegradable. Yes, it really is a pity they are so unsightly.

Time to Plant

Plants in storage tell us when they are ready to return to the soil. The buds on this dry begonia tuber (overwintered in the garage) are telling us the time is right. This tuber will develop very quickly in damp (not wet) soil, especially since this soil will have warmed up considerably in the spring sunshine.

I like all plants to show some sign of life before attending to them. And because they grow more quickly than those planted earlier, there is less time for attack by slugs, fungi and the like. This makes growing more successful.

Normally I plant out my stored dahlias at this stage. I don't know why I put them in earlier this year - especially as the season has kept so cold. Well I do know - it was to get earlier growth. But, as I have said before, things catch up. I bet I haven't saved more than a few days.