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DAHLIAS- commonly asked questions

Updated: Aug 3, 2021

please please research things.

Don't rely on the answers given by myself or anyone else as being the one and only answer. As with ANY gardening matter, there is no single solution to a problem and what works for me might not work for you.

Answers provided are merely my own experience or those from professional growers.

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Q. I’ve bought some new dahlias and they came prepacked in bags. Should I plant them or leave them in the bag?


A. Firstly, use your invoice to double-check your order straight away. You usually have 5 to 14 days dependant on the company to check for damage and request refunds and replacements. Mistakes do happen, so always keep your receipt as the companies will replace any mislabeled tubers.

Working your way through the invoice one by one, remove the tuber/clump from its bag, check them over to make sure they’re not damaged or rotten and if it's dry, label the tuber with a sharpie or vivid, being careful of the necks. If tubers damp, allow to air dry for an hour or so.

Pot each tuber up in a small pot/PB bag short term, in the fresh dry potting mix until Labour Weekend when it’s safe to plant outside. The pot just needs to be large enough to hold the dahlia sideways (dahlias should be planted laying sideways, with the eyes facing up, but don't worry too much as they will figure it out themselves ).

Keep the pots with the dahlias somewhere cool, dark, and sheltered with good airflow. Do NOT water until dahlia has roots and leaves, as they have no way to process sunlight or water without leaves or roots. Watering will rot them and sunlight can dehydrate them.

......................................................................................................................................................................................................................... Q. What’s an eye and where do I find it on my Dahlia?

A. Dahlia eyes are where the plant sends it’s sprout out ( like on potatoes ) . It’s a very small hard to spot raised area near the neck of the tuber. dahlias MUST have an eye to flower. often these are not visible until they sprout. when in doubt, plant it out! it has more chance of growing in the ground than it does in the rubbish bin


Q. My Dahlia snapped off and the tuber isnt attach to the stem anymore, will it grow?

A. The tubers are the battery for the eyes to grow. With no eyes the tuber has no way to expend that energy. for the eye, it has no access to energy with out a tuber. because of this we take great care with handling the dahlias so as to not snap the neck


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Q. My new dahlia is soft with rotten bits


A. Take photos and contact the supplier if newly purchased. If a gift or trade, remove from the bag, check where rot occurred. Hopefully, the eyes and neck are still intact. If the rotten bit is a tuber attached to a clump then remove the rotten tuber using sharp tools ( see photos ) . If it’s a single tuber, scrape off the rotten bits with a sharp sterile knife then sprinkle with cinnamon ( cinnamon is antibacterial which will help it to heal and dry ) or flowers of sulphur or dolomite lime, and allow it to air dry somewhere dry and out of the direct sun for a few days until the wound is healed.





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Q. My new dahlia has a weird white growth on it, is this gall? And what exactly IS gall? is it only on Dahlia?



A. Possibly Lenticels! Lenticels are pores in the skin of tubers; botanically, they are stomates. They are involved in gas exchange of oxygen and carbon dioxide during respiration and photosynthesis - in laymans terms they're just the tubers way of coping with extremely wet conditions.


LENTICELS


 What is gall?

There are two types. Crown gall—Agrobacterium tumefaciens

Crown gall hosts include chrysanthemum, dahlia, geranium, marigold, peony, and snapdragon. The crown gall bacterium causes distorted growths or galls, principally on the basal stem and root crown at the soil line or just below the soil surface.

Gall takes form in two varieties, leafy crown gall, and crown gall. Leafy crown gall is easy to spot due to the abundance of hundreds of leafy thin shoots all coming from a close area ( see photo, courtesy of the UK national dahlia association ).

 

Leafy crown gall is evident below by its many thin shoots - ie 50 to 100 rather than the few you would normally see.



Crown Gall is evident by its bulbous round smooth lumps, normally cream coloured. They can appear at either end of tuber.




Q. I thought we don’t get gall here? A. According to the MPI ( ministry for primary industries) we have both varieties here in New Zealand. If you suspect you have gall you should take extreme caution. gall is not treatable.


Q. What should I do if I suspect gall? 

A. Immediately quarantine dahlias that are suspicious and any that you touched during the investigation as well as tools etc. gall is highly contagious and will infect all your tubers that you touch with infected tubers/ tools that are contaminated. Research to see if you think it is gall, and contact the supplier privately. 

................................................................................................................................................................................................................. Q. My tubers very wrinkled and small, should I soak it?

A. No, dahlias from box stores often look this way but 99 per cent will grow. Small tubers are often better than big ones. Pot them as usual until planting.

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Q. When can I plant my tubers?

A. Labour weekend. 

spring weather often has a last-minute unexpected cold snap or floods- for example, Christchurch recently had a 20-degree day followed by snow the next, and unfortunately, a number of gardeners had frostbitten dahlias. If you really need to plant sooner then use the long-range weather forecast to get an idea on how safe it will be, and use frost covers ( cloche, etc )  and mulch. accuweather.com offers a month's range.


Q. do I water the planted ones?


A. No - not in spring. if planted they will be absorbing what they need from the ground. If you water them they will likely rot. If in tiny pots, then you may need too but don't until they show signs of wanting it.

dahlias - whether in pots or planted - will SHOW you when they're thirsty, they get a droopy dull look . don't be tempted to water

.......................................................................................................................................................................................................... Q. What size pots can I grow them in

A. minimum 30 litre but it depends on the variety. they need LOADS of water in summer in pots so take this into account.


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 Q. How far apart should I space my Dahlias 

A. Depending on the variety, 24 inches apart for a dinner plate and giant dahlias. 12 to 18 inches for everything in between ( smaller plant = less space, do your research to see the recommendations for your type ) 

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Q. How do I stake my dahlias? 

A. For my large dinner plate-sized dahlias that co-exist with other plants, I use the singular stake method. I dig the hole then place a stake of at least 1.2 meters height firmly in the hole before I plant. As the dahlia grows I tie it on using shower curtain clips. I do this three times as it grows so that it's completely supported.

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Q. What can I grow with dahlias?

A. Annuals are great as they give weed prevention until the dahlias are fully grown, and finish flowering around the time dahlias are starting. Then they self sow and flower again through winter and spring as long as you allow them to seed. Roses, geraniums, chrysanthemums etc all go well.


Q. What recommendation can you suggest for Fertiliser? A. During winter I top dress the soil with compost, like, blood and bone.

I feed mine after they sprout with sheep’s poo and tomato slow release fert, but am switching to the bulbs direct fertilizer designed specifically for dahlias. I give lots of worm wee through summer. Epsom salts when they look hungry or pale. ....................................................................................................................................................................................................... Q. When and where can I buy dahlias?

A. Pre-orders begin in summer from a number of growers, then MORE pre-orders are released late June/ July / August. Shipping commences August onwards with each company shipping out at different times. Please refrain from messaging the companies about your orders unless you can not find an answer anywhere else. The growers/suppliers are often out in the fields harvesting, or in the sheds packing, and as long as you received a confirmation of your order then you will receive it eventually. There is always a Mini panic when some people receive dahlias and others haven’t, but please be patient and be aware you will be contacted for payment before they post ( if you didn’t pay on ordering ) and there is often thousands and thousands of orders going out nationwide so it will go out in order of when it was received.


SUPPLIERS:

Some companies begin selling their pre-orders in January, others release tubers for sale in Winter or Spring.


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Aunts Garden
Aunts Garden
Sep 12, 2020

Updated

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Aunts Garden
Aunts Garden
Sep 11, 2020

Thank you!!!

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Great information 😀

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