101 | Zinnias & Snapdragons

Today I’ll be planting semi-double Polar Bear White (Elegans) zinnias with Orange Wonder (F1) snapdragons in one of the flower beds just behind the retaining wall. This plant combination may not do very well together. Both plants love full sun but zinnias tend to like their soil more on the drier side whilst snapdragons may want more watering in the drier spells. I’m trying it out because I saw this beautiful combination from VWGardender and felt inspired to have a go with what I had already grown from seed.

When to sow zinnia seeds

Purely due to time constraints, I started the zinnias indoors in early June which is much later than I would’ve liked to start them. The seed sowing timeframe for zinnias fall between April and May for indoor sowing. Starting them indoors four to six weeks before the last frost date is the earliest recommended time to start them.

Advice from some gardeners is that you can plant zinnias in succession much like you would with gladioli to ensure you’ll have blooms well into autumn or when the first frost hits. The advice is to start sowing seeds between late May until the first week in July. 

JAN	FEB	MAR	APR	MAY	JUN	JUL	AUG	SEP	OCT	NOV	DEC
	Sow under cover
	Plant out / direct sow
	Flowers / harvest

Zinnias and root disturbance 

Zinnias hate root disturbances so I’m not sure how well they’ll fair seeing that I sowed seeds in cups rather than in their final positions in the ground. I did read that growth could be stunted and blooms would be smaller but that seems to relate to breaking apart their root ball by digging them up and transplanting them. From what I understand, if the root ball is kept intact (like growing them in their own containers) then they’ll be fine. 

I wanted to ensure I got a high germination rate so I planted three seeds in each cup. When I had to transplant them two weeks later, I was surprised that they had so much root growth and feared that I may have damaged the plants from trying to separate their intertwined roots. Next time I will only plant one seed per cup. I’ve found that zinnias are super easy to grow from seed so I’m confident I’ll have good germination rates every time.

Initially sowed three zinnia seeds in 4oz cups then transplanted them individually in 8oz cups.

Burying zinnia seedlings

I also learned that zinnias should not be buried in the ground much like you would with tomato seedlings if they became leggy. Well my zinnias were super leggy so I took a chance and buried them up to their cotyledons. 

Edit | it’s July 12th and the zinnias have grown quite large in their little cups. I thought burying the stem would have been somewhat detrimental to their growth but I can see roots shooting out of the stem just below the cotyledons where it makes contact with the soil! So burying your leggy zinnias seem perfectly fine and will make for a sturdier plant. Next year, I’ll try burying some of them just under their first set of true leaves to see what happens.

Example 1 | Roots emerging from an Orange Lime Queen zinnia seedling

Example 2 | Roots emerging from an Orange Lime Queen zinnia seedling

Snappy snapdragons 

I started my snapdragons on March 31st - right in the middle of the suggested sowing timeframe. 

JAN	FEB	MAR	APR	MAY	JUN	JUL	AUG	SEP	OCT	NOV	DEC
	Sow under cover
	Plant out / direct sow
	Flowers / harvest

Sowed snapdragons on March 31st

Snapdragon seedlings eleven days later 

Snapdragons twenty seven days later. Many have two to three sets of true leaves 

I managed to transplant the coloured snapdragons in their own cups on May 10th

I’m yet to transplant the White Giant (F1) snapdragons from their seed trays to their own cups. 

Hardening off

The advice given by pro gardeners is to always harden off your plants a few days before you intend to plant them out. Hardening off plants is exposing them to the elements typically over the space of a week. So on day one, they’ll be outside in a sheltered spot for an hour. Day two - 2 hours, day three - 3 hours etc. I couldn’t harden off any of my home grown plug plants simply for lack of time. 

I grow all my seeds in a south facing window so they are exposed to a few of the elements (sun, wind) from the onset. So far, everything I’ve planted out is thriving and it may be because of the early exposure they’ve had as opposed to no exposure if they were grown under grow lights in a basement for instance. My plugs tend to be leggier than those grown under lights but once they’ve been pruned after being established outdoors, they tend to bush out (for most plants I’ve grown so far).

Zinnia and snapdragon soil mix

I added a few amendments to the soil using my homemade soil mix:

• Peat moss 
• Bone meal 
• All purpose granular fertiliser 
• Compost
• Vermiculite
• Perlite 

I never measure anything when making my potting soil. I just eyeball everything. Typically I’d use 1/2 peat moss, 1/2 compost, 1/3 perlite, 1/3 vermiculite, 1/8 bone meal, 1/8 fertiliser and a sprinkle of lime for plants that do not like acidic soil. This mix works for just about everything I’ve grown so far.

While zinnias aren't particularly picky about their soil, they do prefer it to be fertile, humus-rich, well-drained and with a pH of 5.5 to 7.5.

Snapdragons prefers soil that is

Planting out

I planted five of each plant and arranged them in a zigzag pattern. I added additional bone meal and all purpose fertiliser to the planting holes.

Zigzag planting pattern

Once I got them in the soil, I gave them a good soak to minimise the shock of transplanting. 

The snap dragons are already flowering and new shoots have already emerged so I should be seeing new blooms soon. 

Zinnias take 6 weeks to see the first blooms once grown from seed so I have some time yet to see them flower. I pruned the second pair of true leaves off a few zinnia seedlings (a practice called “pinching” which encourages bushier growth) but didn’t have the time to do so for the snapdragons. Nonetheless, the latter has been developing side shoots and have started to branch out. Next time, I hope to pinch all my seedlings.

For updates (if any) on this specific project, type “101” in the search box at the top of the page.

Q&A

I started this project with a few questions in mind and have since found answers to them either through my own experience or via the internet:

Q: Can I bury my leggy zinnia seedlings?
A: Yes - burying leggy zinnias just under the cotyledons will promote the growth of roots making for a sturdier plant.

Q: Can I bury my leggy zinnias up to their first set of true leaves?

A: (Pending - I will have to try this to see what happens).

Q: Can I start zinnias indoors or do I have to direct sow them outdoors?

A: Growing zinnias indoors in their own individual cups/ containers is fine to do because the root ball will be kept in tact.  Using a biodegradable pot would be ideal so that both plant and pot can be buried in the ground. The roots will be able to grow through the pot and the pot will decompose over time. However, growing them in disposable paper cups works well to do long as care is taken when extracting them.

Q: How far apart should I plant zinnias?

A: The general advice is to plant them 30cm apart.

Q: How far apart should I plant snapdragons?

A: 

Q: Can zinnias and snapdragons be planted together?

A: 

Q: What pest problems will zinnias encounter and what deterrents can I use?

A: 

Q: What pest problems will snapdragons encounter and what deterrents can I use?

A: 

Q: Can I fix bent zinnia transplants?

A: It appears that if it’s staked early enough (whilst the stem is still tender) then the plant will become upright as it stretches up towards the sunlight.

Q: Can I fix bent snapdragon transplants?

A: It appears that if it’s staked when the stem has already hardened then the plant won’t become upright. Perhaps if staked whilst the stem is still tender then the plant may become upright.

======================

Notes

001

When I started this mini project, these were some of the questions I had and here’s what I’ve come to learn from my experience:

Can you bury leggy zinnias

Can you grow zinnias indoors 

Zinnia soil preference, location & watering needs

Snapdragon soil preference, location & watering needs

Pest problems and deterrents

Companion planting with zinnias and snapdragons 

dealing with bent snapdragons

What I did

Planting zinnias indoors in cups in early June 

What I used

Paper cups 8oz as they are similar in size to 9cm pots. John mines seeds sowing compost 

Phosphorus plant food every other watering

Didn’t harden off

Used a mix to amend the soil

Added additional bone meal and fertiliser to planting hole 

Staked snap dragons and a few zinnias