DIY TomTato Grafting Tomatoes onto Potatoes 2015

I'm having another go at growing tomatoes/potatoes in the greenhouse.

You can buy them from a well-known online retailer, this is a) very expensive and b) the potatoes yields are poor (going by their reviews). My aim is to reduce the cost and get better yields and taste.

Last year I got good yields of tasty tomatoes but my potato yield was only average, my best plant gave me this 3.3lb of scabby spuds:



The scabbiness and poor yield I think was due to a poor choice of potato variety and under watering.

This year I'm trialing several different potato varieties:
Cara
Charlotte
Desiree
King Edward
Pink Fir Apple

I'll grow 2 or more of each one, using different tomato scions. Last year I got the best results from Floridity F1. The TomTato plant gave me as many if not more fruit compared to a normal one, and it looked much stronger and kept growing for longer. I think the potato roots give the plant increased vigour.

Last year's thread here: http://gardenerscorner.co.uk/forum/threads/diy-tomtato-grafting-tomatoes-onto-potatoes-2014.64597/

 

I sowed my tomatoes 4 weeks ago, I have just started chitting the spuds, the aim is to get both to the same size, i.e. the potato chit/sprout and the tomato stem.

I'm aiming for mid-April to do the graft. The potatoes will need to be potted up for a couple of weeks beforehand to encourage roots.

The process of grafting and aftercare is a bit laborious, but apart from that the costs are very low, just a few pence for seeds and spuds. The end result I'm hoping will provide two crops in one, ideal if you've only got a small growing space.

 

Go for it Loli, I did OK last year with a late start. Just keep your clumsy brother away

 

Looks good @DRB , what varieties are you trying and what rootstock?

 

Yes, I got a slightly bigger yield from 'normal' non-grafted plants growing alongside (of the same variety). They tasted and looked exactly the same so that's why I'm encouraged to try the Pot/Tom graft on a bigger scale this year.

The main issue is finding the most suitable potato variety, T&M sell these http://www.thompson-morgan.com/vegetables/vegetable-plants/all-vegetable-plants/tomtato/t47176TM but they don't say what variety, I think they have chosen one that suits their grafting production line rather than for yield/taste. T&M got bad reviews last year most people only got a couple of spuds after all that money and effort.

In NZ there is another company selling grafted TomTatoes using the variety Agria, but that isn't available in the UK.

Hence why I'm trying five different readily available potato varieties this year.

 

With tomatoes onto tomatoes I did the same as you, matching up the same size stems when both plants are quite small. With Tomatoes onto Potatoes I was using much bigger plants and that helped me as I'm not very dexterous. I tried a couple of techniques:

1) I had most success with a 45 deg cut on both then clamping them together with a grafting clip (this is not my photo - just one I found):


2) I had not much success with what i called the 'splice' method, this may not be it's proper name. Basically you grow both rootstock/Potato and scion alongside, cut off the rootstock/potato at an angle then make an upward slit in the scion. The scion keeps its roots until the graft has healed, use a grafting clip: (again not my picture):



I'll find some of my photos from last year to try and illustrate how I did it.

 

From last year.

I forced the potatoes to get two or three nice long shoots, nipping out the smaller ones:


Next is my attempt at the 'splice', i.e. potato shoot on left cut at an angle, the tomato on the right. The tomato keeps it's roots (only one or two of these actually 'took' I think the tomato just keeps growing from it's root and never healed, so when I finally severed the tomato from it's root it just died):




Next are all my grafts done, I've used 2 or 3 clips per graft:



Then kept cool and away from light (covered with newspaper) for 2 days, then the next 3 or 4 days gradually letting a bit of light and reducing misting:



Here is the graft healed nicely:



Finally planted out in my greenhouse in 42L pots:

 

I've got a few silicon tubes when I was grafting tomatoes, this photo from 2013:



The tubes are too small for my TomTato stems, where did you get yours from?

My chamber was in an unheated room around 18C.