Each spring, many dahlia growers wonder how they can possibly keep up with the ever-increasing number of new dahlias offered each year.
Growing all new varieties is out of the question for most of us. But we want to grow some of them, at least.
How much can we get for what we can spend? How far can we stretch our dahlia dollars?
Buy Among Four Dahlia Types From Growers To Save
The dahlia enthusiast finds that they can choose among four types offered by growers.
They can buy among the following:
- Root divisions
- Pot roots
- Plants
- Rooted cuttings
From this, one can see that the dahlia dollar will go three times as far with rooted cuttings as it will with roots.
But to take advantage of this saving, the purchaser must have special facilities to handle the cuttings upon arrival.
These include good potting soil and the means of growing the cuttings into a plant in time to set out around the first of June.
Root Cuttings
Rooted cuttings are shoots about 2” to 3” inches long snipped from dahlia roots or cuttings then rooted, usually by dipping into a rooting powder. Then placing them in moist sand or vermiculite for 2 weeks or more until an adequate root system has developed.
The commercial grower ships them wrapped in moist sphagnum moss, and they should be attended to immediately upon arrival.
These rooted cuttings may be potted up in 3-inch clay pots or in-plant bands of about the same size.
They should be watered enough to settle the earth around the roots and then placed out of direct sunlight, but with plenty of air until the roots have taken hold.
This is usually a matter of 3 or 4 days. After that, they may be moved out into direct sunshine.
The best time to have the cuttings arrive is from the middle of April to May 1, although cuttings received as late as May 23 have produced sizable plants and flowers before frost.
They should be grown at a temperature of about 60° degrees Fahrenheit.
Too rapid growth will cause spindly plants to be topped or pinched back before they are set out into the garden.
Some gardeners even set rooted cuttings in the dahlia bed and shade them with a peach basket until they have become established.
Plants
The next most economical method for new stock is plants if one cannot take care of rooted cuttings property.
These are rooted cuttings grown into green plants. Usually, they are from 6” to 9” inches tall and available in 3-inch pots or plant bands of about the same size.
The grower has hardened them off by placing them in cold frames and exposing them to the elements when there is no danger of freezing.
They are more rugged than rooted cuttings and are ready for the garden when received.
It is important to have them delivered shortly before the time to plant them out is when all danger of frost is past.
Plants that arrive in cardboard pots should be removed from the container and planted.
Those which come in plant bands may be set in the ground, plant band and all, so the root system will not be disturbed.
It is good practice to give the plants a thorough soaking upon arrival before planting. They should be shaded until they become established.
If frost is not expected until October 1, plants set out as late as June 30 may still be expected to bloom.
Later in the season, dahlias grown from plants should be hilled to protect the clumps of roots near the surface.
Pot Roots
Pot roots are produced by a dahlia plant the previous year when grown in a clay pot buried in earth almost to the top of the pot.
These may be from 3- to 8-inch pots, and the roots will vary in size from a walnut to a small clump 3” inches in diameter with more than one division possible.
They are allowed to bloom once to make certain of the variety, and then all buds are removed so that the strength will be put into new root growth.
These pot roots are usually full of pep, fast growers, and producers of good clumps of roots for the following year.
Many exhibition growers prefer these to all other forms.
If a variety is hard to winter over, it is much more likely to survive when it is a pot root. They should be planted in the same manner as root divisions.
Root Divisions
Root divisions, the usual form in which dahlias are planted, should be firm and plump with a well-placed eye on the crown and a good neck—the connection between the bulbous part of the root and the part of the old crown where the eye is located.
This should not be cracked or broken. Root divisions are the result of dividing the clumps dug the previous fall. They should not be divided until the eyes appear.
The divisions should not be too large since large roots sometimes produce sufficient food for the growing plant so that new feeding roots do not develop and no increase is obtained at the end of the growing season.
If large roots are received, it is good practice to cut away part of the root farthest from the eye and then sulfur the cut before planting.
The Features Of Four Dahlia Types To Consider
Both pot roots and root divisions can be planted around the middle of May.
They should be placed approximately 6″ inches deep with the eye up and toward the stake to which the plant will later be tied.
They should be covered with 3″ to 4″ inches of earth and the hole filled in as the plant develops.
If frosty weather should arrive after the shoots are above ground, they can be covered with more earth or flower pots.
Early planting usually means a good root system and a well-filled clump in the fall.
Plants are cheaper than root divisions or pot roots because a number of them can be made from a single division. This is called propagating.
Next, there is an element of risk as to whether or not the plant will produce roots.
Most of them do, but some produce only fibrous roots, which are useless as far as another season is concerned.
If plants form clumps, they are usually not as “heavy” as root clumps. They do not produce as many divisions and may not have as many eyes as a root clump.
Finally, they require greater care to carry over the winter than root clumps.
Pot roots are equal to root divisions as far as clump-making properties are concerned, but only a few commercial growers in this country have been offering pot roots, and even these do not have them in all their offerings.
Their production is on the increase because of the general satisfaction they give. This is a typical method of producing roots in Belgium and Holland, where space is at a premium.
For the exhibition grower, pot roots or plants seem to be preferred.
For the average dahlia grower, either root divisions or pot roots will give the greatest satisfaction in the long run.
Blooms will be as large with one as with the other, but the root clumps will be easier to winter.
If one has unlimited means or does not care to dig his stock in the fall, plants offer a satisfactory solution to the dahlia problem.
And if one has the facilities to take care of them, more of the new ones can be added at no increase in cost by procuring rooted cuttings.
Probably the best solution is pot roots or divisions for replacements and plants or rooted cuttings for the new ones.
And new ones we must have if the garden is to sustain interest.